My home server is just an old Pentium 4 running Debian with a Samba share. Windows sees the Samba share as a password-protected network drive (although the userid and password on my laptop and main match those of the server so I don't have to enter anything). So the server is not a complete waste of electricity when not in use, I have it folding for ~100 PPD

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Stats of the server are:
- Pentium 4 Northwood 2.4 GHz
- HP D530 motherboard (Intel 865 chipset)
- Gigabit lan (server's connection to the other PCs)
- 1.25 GB of assorted RAM
- 2x Seagate 7200.10 360GB software RAID 1 for Subversion and OS
- 1x WD Caviar SE16 500GB for my backups (see something wrong here
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I back up to the network drive with the Windows 7 file backup, and for my computer with Vista, I use Cobian Backup
Cobian Backup because Windows Vista file backup is brain-dead. I like the Windows 7 file backup and Cobian because they both use standard compressed files, so I'm not out of luck if those pieces of software stop existing.