Any Number Porting Deals Worth Trying?

So I gave Yatango a 30-day trial and ported a spare number to them one that had previously been on Aldimobile. After the trial I let the service go idle. Now they wrote to me that I have to top up within 5 days or lose the number. I don't really care about the number, but since I have a number available to port, maybe I could try some cheapie special for bringing a number. Any suggestions?