You can help the Linux developers by testing out the current bleeding edge version of Linux by downloading the current version from git:
git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
And then you can compile the kernel normally. To fetch the newest updates you enter the directory (linux-2.6) and enter git pull.
Then if you find a bug that wasn't there before you can find out which patch caused it with a git bisect search. It's relatively quick through a binary search algorithm, it only needs around 14 compiles and boots for about 4000 patches, and the complexity is logarithmic I believe (so it's always relatively quick, even with a lot to test).
Also see this quick intro and the man page.
Compiling really takes most of the time. You can decrease that time by creating a minimal kernel configuration (it's worth it!) with only the features activated that are needed to trigger the bug.
I recommend compiling everything directly into the kernel, you can then just do "make bzImage" instead of make and save the time for making and installing the modules (over and over again).