I have a few £2 codes from Eurogamer accounts during the week and I'm not planning to use them anymore. I tested them and they all seem to work fine (apart from the last one which says invalid code for me, but someone else can test it if they like).
An interesting thing to note is that they appear to work in conjunction with other discounts like "zavvifive" which is £5 off a £50 spend so you get £7 off in total. I hope they are of some use to somebody.
edit - they expire on the 15th of August.