Yep!
I had an EE SIM with £2.70 on it, left over from a PAYG SIM promotion. It originally had £10 on it, the other £7 or so got used up a few weeks back. Now it has 40p on it, which I don't care if that gets wiped off it.
Giffgaff, I had £3 on it, which is now gone - I used it to keep my SIM active, as Giffgaff is a good way of testing how good (or bad) the O2 network is in my area.
I was listening to Capital FM earlier today and they did a return of their "Cash Call" competition whereby you listen out for a given song, and keep note of how many songs played up until and including the song from the artist you are listening out for. You then have the duration of the track to text in - afterwards a winner will be picked at random to win the money.
Here's a link to Capital FM's website, about the competition:
http://www.capitalfm.com/win/capitals-cash-call/Didn't win but at least the leftover credit on my SIMs went towards that, rather than simply expiring!
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