Once a year I go back in time. To a time when it was perfectly acceptable to be at the pub at midday, where the biggest decision was whether or not to attend to that 10 am Friday lecture, and where one person’s ongoing refusal to do the washing up could unleash World War 3.

After graduating five years ago, my university friends and I scattered ourselves around the country. Whilst a few continued to live near each other, and reconfigured friendship groups to merge old members with new, contact with most of the uni crew fell to the occasional group email. Even those were often greeted with error messages or ignored as people found new jobs, moved out of home and began their adult lives without pausing to check obsolete hotmail inboxes.

But when someone, missing the old days, had the bright idea of a reunion, we managed to track down almost everybody. Miraculously, this disparate group who previously couldn’t even organise who was going to the offie, got ourselves to the Suffolk countryside for a weekend of camping, drinking, and outdoor pursuits. A few months later the emails started up again, and someone else volunteered to arrange things. This time we blagged a big rundown cottage on the beach in Cornwall from a friend, filled our days with boardgames and beer, and the annual tradition was well and truly cemented.

At university my group of friends was a particularly tight, if rather large clique. Incredibly, the people sorting through the halls application forms got it completely right. The girls of E2 high and the boys of E2 low, two adjacent flats in a dorm which, legend has it, is modelled on a Swiss prison, got on like a whole street of houses on fire, and in some cases didn’t feel much of a need to make any further friends for the rest of their time at uni.

When we meet now, it’s like the years since then haven’t actually happened. Evidence of them seeps through, of course; someone’s girlfriend is pregnant, a couple are engaged (although not to each other), someone else has a powerful job in TV. But there’s no need to talk about what we’ve been up to, at least not in any detail. It’s an extreme version of when we used to return after the holidays, with the weeks spent back at our parents’ homes feeling unreal and dreamlike as soon as we set foot in the Student Union. I’ve just returned from the most recent reunion - four days in a converted barn in Staffordshire - having only a patchy idea of what at least half of the attendees do for a living. And that’s kind of the point. When we get together, the old chemistry that made us mates when we were students still works, and we slip back into those easy rhythms, rendering our current careers and love lives irrelevant. Silliness and endless games tend to prevail instead.

Great as it is to revisit those times, there can be potential problems. People have changed in the last five years – but stereotypes persist. It’s slightly tiresome to expect the same person not pay their way, know who’s going to whip off their jeans to reveal a pair of comedy pants, and predict who’s going to offer to/insist on doing the cooking. When we were younger there were tensions too – people got involved, or developed intense irritations with one another, often both, almost simultaneously.

But even though we don’t spend long discussing the years since university at reunions, that time - and geography - have given us enough distance for old issues to no longer matter. Instead we have an opportunity to remember just how well we got on, all that time ago. Possibly trumping all of that though, is the fact that these days people realise helping to clean up is preferable to having a kitchen so putrid that the halls cleaners not only refused to go in there, but wrote a letter to the Union about how disgusting it was that they were expected to. Bad students. Good grown ups.

One of the strangest aspects of university is that the world students create and inhabit, a world bursting with brand new, never-felt-before emotions, ends so suddenly. I vividly remember my last night at Leeds; my possessions were boxed up in my room, and the memory of finals was already blurred by an alcoholic haze of late nights. We went to a club - it was a fun, drunken, any old kind of an evening, and afterwards we all piled back to someone’s house for tea and takeaway. It didn’t register until I was standing up and saying goodbye that I would never ever do this again. These people who had been my life for three years simply wouldn’t be any longer. The close-knit gang, the nights out, the communal dinners I’d taken for granted had finally finished. It was done and dusted. And that was harsh. It took me far longer than usual to drive home the next day, most of the journey spent in a carpark on the outskirts of the city, where I’d taken refuge as I sobbed and sobbed, incredulous that it was utterly over.

Still, it’s easier than ever to stay in touch with old friends nowadays. Texting, emails, and social networking sites facilitate even the most half-hearted attempts at contact. Whereas once a friendship required at least occasional phone conversations, now there exists an easily navigable sliding scale of effort and commitment. From a long detailed email to a two-line message on someone’s myspace profile or Facebook wall, there is something for everyone. We all have ‘duty friends’ who we don’t actually like that much; the occasional Facebook poke is now all that’s necessary to let them know we’re still alive, without having to listen to anything they’ve got to say.

If Friends Reunited sparked the craze for digging up old mates, Facebook’s fanning the flames. Rachel, an accountant from London, recently set up a School Reunion Class-of-96 group on the fast-growing social networking site. Within less than a week, it had 50 members; over half the year group, and a date set for meeting up.

These one-off, large scale reunions from further back in the past can bring their own dilemmas. Whilst possibly fun, and particularly satisfying to the nosier among us, there are also the dangers of seeing old crushes and boyfriends, inevitable comparisons of status-markers like jobs and houses, and plenty more besides. One of Rachel’s friends is confident, successful, and gay. She’s been completely out to friends, family and work colleagues for years and has no issues with her sexuality. But she finds it strangely nerve-wracking to contemplate going to the reunion and coming out again to the popular kids she was once intimidated by. She’s hoping that everyone has seen the heart denoting she’s in a relationship with someone called Samantha on her profile, and she won’t have to.

But beware, because this kind of public profiling could have implications for the future, as well as helping connect with the past. Bosses have admitted searching social networking sites as well as googling potential employees. Will it really look good for the professional world (not to mention the dating one) to know that the almost inconceivably geeky, frizzy-haired boy in the ancient school photo is you? Or see last weekend’s snaps of you in fancy dress at a party, or hot, sweaty and losing it at a gig?

Even if you take that into account, and either eschew the phenomenon altogether (unlikely) or ensure that your profiles are never too personal, there’s nothing to stop others tagging you in photos without your knowledge. Most people would prefer the pics of them in that awkward teenage phase to stay private, rather than be posted with lots of lols on their myspage page. My friend Nathan finds it exasperating that other people tag him in Facebook photos without asking him first. He makes it his (rather time-consuming) business to remove every tag as soon as it appears and let his friends know not to tag him in the first place. (Obviously everyone completely ignores this. Knowing it gets on his nerves makes the activity vastly more amusing.)

But, as I write this, another friend is enjoying a hot weekend in Sicily with an old flame who found her on myspace. Once upon a time, not getting it on the first time round would have meant he’d have missed his chance. Now, you can always go back; nothing is ever too late.

When those final exams are taken, the shared cutlery and crockery divided up, the last squabbles about bills all sorted out, when people pack their belongings into cars and trains and coaches home, there’s no need to despair. Making the effort to meet once in a while is worth it; it allows those carefree university days to live on, occasionally at least, in the that scary place: The Real World.

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