Updated Honeyd for Windows
Honeyd, originally a Unix/Linux-only product by Niels Provos, is one of the best virtual honeypot software programs in existence. It is very flexible and useful. Michael Davis did the original Honeyd port to Windows (thank you very much, Michael), but that version didn't keep up as Windows XP and later came out. Changes in Microsoft Windows and a few other notorious bugs made it hard for me to ever recommend using Honeyd for Windows over the last year or so.
Instead, I'd suggest that people use the Unix/Linux version of Honeyd, but that meant learning new skills if you were a Windows-only person. Or they could use Kfsensor.
Jesper Jurcenoks, co-founder of netVigilance, has released an updated version of Honeyd for Windows. You can get it at the netVigilance Web site. Jesper and his company took the time to do a complete rewrite and free update of Honeyd for Windows. He even corrected one bug that remains in the Linux/Unix version to make sure it didn't get replicated to the Windows version, and netVigilance offers a $99 GUI configurator, which can save you hours of configuring and troubleshooting. Thanks to Jesper and netVigilance (and Michael Davis for his earlier contributions) for allowing us Windows security types to play with Niels' excellent honeypot software.
CaptureBAT is a neat, free tool for Win32 honeypots that analyzes file, registry, and process information. It's an excellent addition to Sebek in that it provides far more information. It works on all Win32 systems, including Vista, and comes with the ability to exclude predefined types of activity (which is a must when you're doing real-time file and registry analysis).
Capture-HPC is a high-interaction honeyclient. The New Zealand Honeypot Project, which produced Capture-HPC, also wrote an excellent white paper on using Capture-HPC to identify malicious Web servers. The group includes the paper, data, and tools for anyone to replicate, and it inspected more than 300,000 URLs (nearly 149,000 hosts) found on 194 malicious servers. It's an interesting read.
If you haven't investigated the honeypot world in a while, this is the time to come back and get involved.