I've enountered people who claim it is impossible to use vector based icons at the size of 16x16 pixels, but I don't think that is the case at all. Sure, it can be frustrating, but at times, it's also liberating.

I tore my hair, switching back and forth between different scales, until I found out that not only should (and could I draw the icons at 100% size in Xara X, but if I placed the vertices at integer/decimal positions, I could control the anti-aliasing! I think that is my most important tip to share.

Does anyone else create icons like this, and have any tips or images to share?

Here's a recent one of mine (from a selection of about 150 buttons, I think):

http://www.eobet.com/temp/work-detail.png

These were especially tricky since the legacy of the application look & feel dictated black outlines around every object, meaning that in essence, these are really 14x14 pixel sized icons. In the future, say with SVG icons, it would be great to be able to set an outline to be exactly 1 pixel thick no matter the scale, because these really need to be tweaked for different sizes now in order to not get out of proportion.