A LEGO store recently opened here in Glasgow and they have a 'pick and mix' section where you can buy handfuls of different bits of LEGO, although I didn't check to see how much they were...
I used to (and still do) love an old computer game called Sokoban, which roughly translates as warehouse keeper, and I thought about how to make a board game version of it - I had the idea of building a board out of LEGO, and it seems that someone else has had
the same idea already, so I need to get myself down to the LEGO shop and buy some bits, and then figure out how I'm going to do it. Part of the problem is that Sokoban is like Minesweeper in that it is hard to imagine how you might play it manually (since alot of the fun in Sokoban is being able to explore different moves and 'delete' previous moves etc., as well as keep score of your moves), but I think it could be done - and the big advantage of LEGO is that you can build loads of different 'levels' relatively quickly.
Anyway, if anyone has any suggestions, let me know - if I get round to building a board/set, I'll post the results here.
edit: Here's a screenshot of the game:
I need to think about what bits of LEGO would be best for a board like this... the man can only push the gems and not pull them, but the gems have to be able to slide from square to square.