I'm 100% sure I'm telling no one anything new in this post. Still, I feel I must mention this. Everyone who is seriously developing at home on his own computer, and not to a company server through some VPN, needs to have some sort of source control. There are many options out there, right now I'm experimenting with a combination of the following two:
* VisualSVN - visual server, free for personal use. 500$ per server for enterprise version.
* AnkhSVN - visual studio plug-in
My official real career (where I get paid to work) experience thus far with source control environments included perforce and sourcesafe - there were a few others I'd rather not mention as well. Obviously, usage of the two freeware apps listed above is far superior to SourceSafe - which people from within Microsoft have always made fun of themselves.
For those who have no clue as to what I'm talking about - source control is a database system used to archive changes in code, allowing tracing of when and who added changes/bugs and tracking versions and releases. Assume you wrote something awesome and cool - and then one day you just edited a file and destroyed it's functionality, without source control - there'd be no way to restore what has been achieved thus far.
PS. There's a free E-Book for subversion, including PDF downloadable version: here.
PPS. Of course, if one is comfortable with going public with his development phases - he may choose to host on sourceforge.net, and use their source control management which include subversion.