Yesterday I launched a website called The Ultimate Unit Converter. It's a unit conversion tool that anyone can contribute to (a bit like wikipedia). This came about because I had previously made SensibleUnits.com and didn't have time to implement all the great suggestions people would send me.

Many years ago I used to post on the old BA forum (although I was mostly a heavy lurker), and was always impressed by the intelligence and knowledge of posters there. Hopefully I'm now right in thinking that some of you might be interested in contributing to this project. It would be fantastic if you could add any scientific units that are missing (any non-length units, for a start!), and also submit any real objects that you think might make useful comparisons. Cheers!

P.S. My sincere apologies if this counts as spamming or such.