i would like to test my knowleagde, where will i find some rather simple tasks to do?
im not talking about things like writing os or anything complex. just to make sure i understand everything from the manuals and im ready to go forward.

Demo OSes are pretty popular 'round here. Write a demo OS that does something cool.

b1528932,

With regard to your recent interest in SMM, simple viewer for PCI configuration registers can be both challenging and useful.

simple viewer for dos or bootable.
using only real mode bios capabilities.
just to be the more compatible with every machines.

write a Hex Viewer.
i know there are alread some (good) ones,
but try it.