Familiar with the Angry Birds? Not sure? It's a very addictive game from Rovio made for N900 and some other mobile devices.
The free version only contains level 1 and for you to play level 2 and 3, you need to purchase them. But for N900 users, I have the pack for level 2 and 3.
To install it on your N900, make sure you have the game first.
Then download this file. Extract and copy the two files inside to your N900 memory (you can put it anywhere).
Then open the file using file explorer on your N900.
Ta-da! Free games for you.
Hope that clear things out.