Hi Hawk,
this one is tricky. If you're serious about doing this you're going to have to discipline yourself as far as night life goes. That's obviously where a large proportion of your dosh is going to go.
You can get a student railcard that will take you round most countries in Europe for a certain length of time. It will even get you on ferries or at least get them discounted.
Youth hostelling is the way to go as far as accomodation goes and you may meet up with people who can get you a bit of cheap labour. Avoid lugging a tent around Europe!
Also, maximise your money by avoiding bank charges on cash dispenser withdrawals and travel vouchers. Find out which bank will service you best in this respect. Don't travel with all your money. If it gets knicked in a Hostel that's your trip over! You may want to look into an overdraft facility if you're happy with the thought of spending two years paying it back! Still, as you say, you don't often get the chance to get away and do something llike this. Now IS the time, because once you're stuck in a job it is very hard to find the motivation to do this.
There are some great books out there to help you plan a trip like this. Remember, planning is everything! ?'Lonely Planet' do a very good book called ?'Europe on a Shoestring'. You can get this on Amazon for about a tenner. It'll give you ALL the info you'll need including places to AVOID!
You're also going to have to plan what you're taking with you. Get a good sturdy pair of walking boots. Remember over six months you'll encounter many different weather conditions. Take thermal underwear! Sounds silly, but they're very warm and LIGHT. Most hostels with have laundry facilities so you don't need to take 50 t-shirts with you. Take trousers that have detatchable lower legs. This'll save taking trousers and shorts.
Buy your medical stuff in Britain, it'll be much cheaper. Also arrange travel insurance. Try this link
www.insureandgo.com/Travel-Insurance/Backpackers-Insurance.htm
You can also get an official Insurance form at the Post Office which is free. Search on the Post Office website for an E111 form. You'll get all the info you need there.
Get a skinny wee camera. Also, take a diary to chart your progress. When you're older you'll wish you had!!! Besides, if it is REALLY action-packed you could get a novel out of it! People love a good travel story!
Finally, have great time! Europe has a LOT to offer. And don't forget to head north as well as south. It's easy to head for the Riviera's but Scandanavia is equally as gorgeous!
I do hope this helps.
Cheers,
imperial.