* 10MBit of userpics per second (or 100+ pics per second)
* Dual Xeon 2Ghz
* thttpd serving 20M pics directly from a plain /userdir/userpicid/ filesystem. Let's assume that there is no preference on certain pics and that they all might be servered randomly.
how much RAM would the server need minimum (would it even make a difference...)? would scsi be enough or would a raid be necessary? how much further could it scale up to?