I called into tesco last night and noticed they had a bit of bike stuff to clear. I bought a mini rear LED light (ideal for helmet) for 99p, which was reduced from about £3. They also had lots of innertubes (only for 26" and 20" mountain bikes unfortunately, I would have bought all the road bike ones if they had any) for only 30p each. Plus a few more cheap bits that could come in useful.
Might be worth having a look
Edit- Oops just seen SimonR's post above. Although it looks like things might have been reduced further now though
Might be worth having a look
Edit- Oops just seen SimonR's post above. Although it looks like things might have been reduced further now though