I have a late 2013 21.5" iMac with the standard pedestal stand. I've been trying to figure out a way to retrofit it to a VESA type mount, to mount it on a wall instead of sitting on a desk. So far the only thing I've seen is an adaptor that still leaves the pedestal stand attached.
http://www.imacmount.com/index.html
Although its no doubt functional, I think it looks hokey and would prefer to do away with the pedestal stand altogether. I didn't realize that a VESA option was available when I bought my iMac, otherwise I would have just ordered it that way. I contacted Apple directly (corporate) and asked them if they could retrofit mine with the VESA option for a fee - they said that they would not.
So if this is possible (which I believe it is, based on photos of the same iMac disassembled), who does this kind of work? I'm looking for the ADCO of the computer world, lol.
Thanks!