I got 2.99% cheques on the RBC Avion! !!!! (Until May 31, 2008).
Really, I could put 100% of my credit limit into ING direct, and collect the 0.50% spread for half a year, and make a little bit of money with no effort.
There don't appear to be any processing fees with these cheques. Every credit card I have seems to send low-interest cheques, usually lower than 2.99% and usually with extra fees attached. BTW, PCFinancial is paying 4.1% plus a small year-end bonus, which isn't a bad return on these cheques (still assuming there's no extra charges).
=aw