According to the Glastonbury Festival countdown clock right now as I type there are 11 hours and 1 minute until the festival gates open. I've never been to Glastonbury Festival but I do have some fond memories of some of the performances I've seen from the TV coverage. It's good that they cover it on TV nowadays, when I was younger it was never broadcast on TV - it might have been on the radio I suppose, but I never heard it if it was.
I did attend a festival for a few years running in the early/mid 90s. The music lineup was really good and I saw some great acts. But the downside was that I didn't have any friends to go with and so I felt a bit lonely on my own, as everyone else seemed to be enjoying themselves with friends and generally having a big party, staying up into the early hours, sleeping most of the day etc. I have some good photographs I took of the people and one day I'll have to scan them in and post them up here. I was afraid of being in my tent alone at night, having the stuff in my tent stolen and all sorts of violent thoughts go through your mind. But there are some really nice things too: the people are generally very friendly, you see lots of people with weird and wonderful tattoos and piercings, strange looking hairstyles and clothes - and you get to see some strange behaviours too - whether drug induced or not. I would recommend at least trying one music festival out during your lifetime.
I hope the weather stays dry for the people this year.