I found a site where you can play a massive range of ZX Spectrum games through flashplayer (ahh... the nostalgia!). However, there are two main problems with it:
1) You have to sort of mash the keyboard to work out the controls
2) God, the games are crap! LOL! I can't believe many years of my youth were consumed with loading these games for an hour, but hey... we didn't know any different!
Unfortunately, the link is added to my favourites on my home computer and I can't remember the name of the bloody site!