Hi
Configuring grsecurity was a breeze, but going recursively through the bazillion options the kernel provides was not. So in case anyone is interested I've setup a github repo with rather lean kernel configs for KVM and XEN (the XEN one works on a Linode). Hopefully it'll save someone else's time.
Those kernels have been in production for some months without any problem but as always no guarantee provided.
Suggestions/forks/pull requests and configs for other setups are of course welcome.
https://github.com/taradiddles/grsec-kernels
[EDIT] - I've also uploaded a script I've written to automate building, it automatically fetches the latest kernel and grsecurity patches, extracst/patches the kernel, and optionaly builds a kernel with a supplied .config file
Ivan