For those of you with twitter accounts, @TeamMatchbook are doing a few competitions per day (with prizes presumably of declining value representing the length of the promotion). All you have to do is like and retweet the post, and you have a chance of £/$/E 38 added to your balance. I’m only posting this because hardly anyone is entering – you can obviously tell from the number of likes and retweets – and I won £39 yesterday.
There’s one there now, closes at midday, when they’ll probably do another one closing at 2pm (and repeat).
I guess you’d need to have an account already registered.

Your first 30 days for just £1