The Auto Nice Daemon activates itself in certain intervals and renices jobs
according to their priority and CPU usage. Jobs owned by root are left alone.
Jobs are never increased in their priority.

AND is very flexible. The renice intervals can be adjusted as well as the
default nice level and the activation intervals. A priority database stores
user/group/job tuples along with their renice values for three CPU usage time
ranges. Negative nice levels are interpreted as signals to be sent to a
process, triggered by CPU usage; this way, Netscapes going berserk can be
killed automatically. The strategy for searching the priority database can be
configured.

AND also provides network-wide configuration files with host-specific
sections, as well as wildcard/regexp support for commands in the priority
database.