Hi, i have a small NAS box (exito B3) running a ARM cpu, the system is debian squeeze ( armv5tel ). It seems to me that there is no rosetta@home work units for that cpu architecture.
Seti@home has work units for ARM based systems.

Thats in my opinion a bit stupid, because there is thousands of those cpu's in daily use. In the excito B3 case, it is always on and
connected to the internet at all times.

The Exctio B3 specs is:
1.2 GHz ARM and 512 MB DDR2 RAM.
Disk sises 40gb(ssd disk),500gb,1TB,2TB
Two Gigabit Ethernet NICs
2x USB 2.0
1X eSATA
802.11abgn, dual band, MIMO ( option )
Power use: 5-13W (from 5W with SSD, from 8W with HDD)