I have read various post about dual boot setups.
People booting Qtopia or something else ( PdaXrom, OpenBSD etc.) on the same unit - using a boot manager prompt. ( Boot can be from CF, HD or SD)
See for example here: http://www.oesf.org/forums/index.php?showtopic=13560&st=0
Has anyone done this on a C3100? If yes, could you please post step by step instructions?