Sourcegear has an SCM solution called Vault that has a few big things going for it as a VSS alternative:

• You can import VSS projects
• It can work alongside VSS, so you don't have to import all your VSS projects
• It's easy to use and familiar to VSS users
• It integrates into the Visual Studio IDE (if you're into that)
• You can connect to it remotely over HTTP or HTTPS
• It's cheap (free for a single user, $300 per user after that. VSS is ~$500/user)

I'm working on a small project now where the other developer is using Vault for source control, so this gives me a good chance to check it out. I'll also probably use Subversion and VSS 2005 for other projects.