Jenbo just posted this but since I wrote it up already and he left out a few steps excuse the double.

First things first, if you get errors when you do startx youll need to delete 4 files
Code:
cd ~/.kde/cache-root && rm icon-cache.kcache plasma_theme_Volatile.kcache
cd ~/.kde/cache-bt && rm icon-cache.kcache plasma_theme_Volatile.kcache
Now we need ssl devs and kernel headers
Code:
apt-get install libssl-dev linux-headers-2.6.38
Go here http://developer.nvidia.com/cuda-toolkit-40 and grab these 2 files
"Developer Drivers for Linux (270.40)" and "CUDA Toolkit for Ubuntu Linux 10.10"

chmod them and throw them in the /tmp, then "End Session" because we need to do it from cli

For the driver we need to point to the headers
Code:
./devdriver_4.0_linux_64_270.40.run --kernel-source-path /usr/src/linux-headers-2.6.38
Then do the toolkit "no need for headers .. enjoy the matrix "

Before you boot back into X you need to delete the same 4 files from the top!

To install pyrit we have to switch to python27 with
Code:
python-switcher --python27
Now just grab pyrit and make cpyrit first
Code:
svn checkout http://pyrit.googlecode.com/svn/trunk/ pyrit
To make sure its workin just run pyrit list_cores

Cheers