Download version 2011-07-11:
http://www.mediafire.com/?k404b6lqn8vu6z6This could be the last version, because there seems no more room for big jumps. I thought I could remove some more additions, but the OpenCL compiler does a better job than I

. This version is faster than all previous kernels (uses the least ALU OPs for 69XX and 58XX). Should also work with SDK 2.1. If it throws an error with 2.1, please post here and include the error message!
Thanks to all donators and your feedback!
Dia
This one seems to act rather strangely.
On 2011-07-06 I had a pretty consistent 360MHash/sec with little variation. With 2011-07-11 the card is varying dramatically between 355-363, and usually at the lower end of that. Overall it may be slightly slower.
The cards are 5850s clocked at 900/300, using 11.4 and SDK 2.4 on Linux.
I'm going to let it run a while longer.