I would love to try experimenting with making one (or more) of these things a "swap box" for a PS3 running linux. One of the main problems with the PS3 is that it only has 256 MB of RAM.
Hard drives takes on the order of a 10ms to seek. However pinging something on an ethernet network takes 1ms or less.
Therefore there is a possibility of getting a significant performance improvement with applications with large data sets.
Unfortunately since anything that touches the hardware has to go through the PS3 Hypervisor, there is a good chance that the overhead will make the whole effort moot.
I'd like to try out two things:
1) Have the MicroServer export a RAM disk as a NFS share
2) Export the Compact Flash drive as an NFS share, and try to modify the kernel so that it uses as much RAM as possible for a cache, only writing the least recently used data to the disk when it's out of RAM.
This is an interesting hacking project. Success depends on how much data you need to swap in and out. What I'm missing here is the actual hardware strain, as the OpenMicroServer has well shown that it can handle continuous RAM and CPU operation over hundreds of days. My only concern is rather the CF card write limit.
Now, if you would mount that PS3 into a helicopter or a Formula 1 car... ;-)