I've attached a source to a program...
Add the usual sort of "no support, no warranty, no guarantees that it won't break your system" disclaimer here....
On some flavors of UNIX, the "quota" command should do it. "quota", with no arguments, should report, for all local file systems with quotas, and all NFS file systems not mounted with "noquota" (and mounted from a server with a quota daemon), quota information for the user in question.
Well, no, actually, it should just report the ones where you're over your quota.
"quota -v" should report on all of them. (Unfortunately, "all of them" may include those that were mounted with "noquota", which means that if the server is down, you may have to wait a while until the RPC calls time out - it appears to mean that on SunOS 5.x, at least....)