Since there seems to be so much interest, here it is.

This package includes a few sysctl kernel tweaks (those are mine), microb tweaks from Brontide's thread, and removes metalayer-crawler from startup.
I advise to have a swap file enabled, any size from 32MB will do, for memory hungry programs.
It depends on ramzez-init, since a ramzswap improves performace quite a bit in general. You must install it first.
This comes from my own setup, and I'm quite happy with it.

Expect no miracles. The N810 is what it is, maemo4-diablo is what it is.
Also, nothing comes without cost:
media player playlists won't work
memory hogs (*cough* firefox! *cough*) can perform worse a bit sooner
microb will load pages somewhat faster, but on some pages (most notably gmail) performance will degrade. If you want a fast browser install opera.

Uninstalling the package will restore metalayer-crawler at startup (if you had it disabled previously you'll have to disable it again), previous sysctl settings (if any), and microb previous settings.

All source code is included in the deb, since it is just a few scripts and text files.