For Virgin mobile prepaid customers. Visit the Members Lounge, right hand side of the screen, scroll down a little to opt your number in for 20% bonuses on top ups made between now (I assume when you opt in) and 31 Dec 2010. Bonus is to be paid in Jan 2010 and they say they will email us about it then.
Feeling a bit miffed as tried visiting the lounge for the first time after I topped up 2 phones :S
Anyways good luck to everyone with it.
Cheers Foundit. It would be nice if they prominently advertised this instead of hiding it away on their website. Not to take away from your find though, thanks very much! Just signed up me and the missus.