Last night I got my first puncture since I starting communting by bike (about 5 months in total) Luckily I had already done 7 of the 8 miles to the station, so I just walked the rest of the way. Nothing got stuck in it, I just wore through the tire. I knew it was on its way out but I'd been putting off replacing it as I'm planning on getting a new bike soon. Looks like I put it off too long. Unfortunately I had to go to Halfords to get a new tire on my way home, in order to get to work today. I also bought an inner tube so I'd have a spare and it turned out to be the wrong size. I even asked the guy if he was sure it was the right size as I'd had problems with them selling me the wrong thing before. They really are useless, its like the bike equivalent of asking for computer advice in PC world. I think I'll stock up on spares from a local bike shop one saturday so I don't have to go in there again.