Here's a short list of handy development tools used in Jitbit and useful for any startup:

Microsoft Visual Studio 2008 Express Edition - this edition is free. Just like our next item....

MS SQL Server Express 2005 or 2008 which is a full-blown database server despite of the name. The only thing I miss in the Express edition is jobs, but they can be easily emulated.

Ankhsvn - a free Subversion plugin for Visual Studio. And consider buying some storage from an SVN-hosting provider. There are plenty of affordable solutions, even the free ones.

IcoFX - a great free icon editor. The one built into Visual Studio lacks the alpha-channel compatibility.

TrueCrypt - a free open source disk encryption tool. All our source codes and sensitive customer data for Hosted Helpdesk and Hosted CRM is stored on encrypted drives maintained by this tool. The drives are easy to backup by the way - just make a daily copy of the container file. This great security tool can even crypt your C: drive on the fly.

Microsoft SEO Toolkit which I already blogged about.