Humble Bundle are selling 5 games in a pack, but you decide how much you buy them for. Could be as low as 1p
The games are
Machinarium - which I highly recommend, is a beautifully done point and click game
Osmos - A very relaxing game
Braid - A highly rated platformer
Cortex Command
Revenge of the Titans
(I don't know much about the last two tbh)
It is all for charity though, so probably best to give a bit more than 1p 
and they work on all systems (Mac, PC, Linux)
The charity is Child's Play, who send games and consoles to children's hospitals so that the children have toys to play with while there. So a really good cause!