skykooler shown us four operating system on Nokia N 900, sit back and see this 2x video by him also he placed How to guide at this link.
Five thinkg your really nedd to do this.
1. Nokia N900
2. MicroSD card, at least 4 GB
3. MicroSD card, at least 8 GB class 6 (I used a class 10)
4. A computer that you can reflash from if necessary (i.e. not running Vista or Windows 7); also one that ...