Back in the Window 98/NT days there was a part of the registry that couldn't be accessed through normal access. However if you ran an executable under the At command (to run it at a certain time), it seemed that At ran processes at system level and could access that part of the registry.
Quartz.net reminded me of that, not because of secret registry access but as a way of scheduling tasks. Linux systems have Cron to let them run a process whenever but apart from AT and later on the Task Scheduler (which can be a little fiddly), you need to roll your own. Or you could try using Quartz.net which is a.NET implementation of the Java Quartz project.
It uses a database to hold the scheduled jobs, and works with SQL Server,sqlite,postgreSQL, MySQL and Oracle. It isn't quite fully released at version 1.0 but beta 2 came out about a month ago so it can't be far off.
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