Scheduled remote wake up multiple computers?

There is never a convenient time to run backups of individual user desktops. We don't use profiles on our domain as it's too slow to log on and off as we work with very large files.

I don't have the funding to have a fast NAS setup as the location of redirected desktops along with a backup solution for that. This would be my ideal solution.

Critical data is backed up every night on the server but user's desktops are too big and don't get backed up. We tell all users to ensure their critical files are on the server and not their desktop, but it's nice to have desktops backed up, work in progress is sometimes not copied to the server. A weekly backup would be sufficient. Even then, if I used incremental backups then night backups could be done over night.

So I came up with this idea.

1) Remotely boot all computers over the weekend.
2) Windows XP scheduled tasks runs ntbackup copying data to a cheap slow NAS we have
3) After backup computer shuts down

Does anyone know of a free or cheap tool to boot multiple PCs using Wake on lan. Also it would need to be schduled.

Could a batch script be written to do this?

I know this post is pretty vague but I could ramble on for years adding keywords and explaining it.

On a less frequent basis I can run a network location backup to tape so the regular updates are on the NAS and readily recoverable. And perhaps monthly a tape backup is available should the NAS and desktop get destroyed.

Hopefully this post will get seen!

I know there are lots of points of failure will this solution but it would be better than the current situation of no desktop backups!