When you work in a team, obviously you need some sort of Source/Version control. I’ve used two such tools - Microsoft SourceSafe, and Perforce. Perforce was a great tool, by the way, much better than SourceSafe.
On smaller software projects though, it’s not so straightforward to use a version control software, as it can be slow and can complicate your work. But it also has advantages even when you work alone.
I decided to take a look at a new version control software - SubVersion. It’s open source, free, and I have heard good things about it. Installation was quick and easy. I also installed a neat client called TortoiseSVN, which integrates into your windows explorer. There’s also a good Plugin for eclipse (which I use for PHP and Java development). SVN uses the Apache server, so if you already have it working, it’s easy to install.
So after only a few hours I had my latest PHP project working with SVN. I have yet to integrate it with Delphi (and I’m not sure if I can) for windows development.