A great tool to convert protein mass to moles!

I stumbled upon this tool a while back and it was on a post-it in my office to tell you guys about it.

I run into this all the time:  "I have x ug of protein, but I normally inject y picomol.  Sure, the math isn't that hard.  But I'd much rather have it done automatically so I don't misplace a decimal place on a napkin and then end up injection 10x too much protein.

This tool makes it easy.  Its at a site called "Practical molecular biology," and I think it might be a site set up by an institute in Russia a long time ago.