Don't! Don't retire it.

I have 2 N900, one 100% functional and one with broken USB. So you can say the one with broken USB is retired. I use it as a media center in my car, as navigation, when @ home, sometimes even watch movies on it connected to my TV (moved all movie into the eMMC with WinSCP).

This is a great device, I am so sorry they stopped, 800 and 900 devices were the gods of all handheld devices!