Do you mean The R4 Revolution card? http://www.gamesbackup.co.uk/ . You load whatever games you want off one of the free sites. (Not that I've done it, but I know someone who has!) I think sites are making it harder to do it so it might be worth checking first. Look on You Tube as to how to do the downloads - there are step by step tutorials on there.
cheapest here r4 or dstt usually come with 2gb card which will fit 30ish games on. obviously the bigger the card more games http://www.dealextreme.com/
There's a little shop close to market in Wombwell They do the Dstt cards but i don't know price or if they come with a memory card in them. but remember unless you buy them online they will be blank. I used to get mine from copy cats in Rotherham.
