QubesOS – A reasonably secure operating system

Last time I tried to throw it on an old box it couldn't handle it due to the lack of IOMMU. Granted this was like... 5 or so years ago? I think my newer laptop could probably handle it, so maybe it would be worth giving another shot.

There are ways to get it running without an IOMMU, mostly involving making your NetVM and such paravirtualized. You just lose basically all of the hardware isolation benefits there. But for playing around, especially on a trusted LAN, you should be able to get it working. If you can't figure it out, jump on the IRC channel - there are a few people in there pretty good at weird hardware hacking for Qubes.