Hi Joacim! I am not too sure, but I have seen 3 letter .orgs going for $60ish (with letters such as q, x, z). If you are looking at 3 letter .orgs without these letters, they might worth $200+ at all wholesale price.
I would say that 3-letter .org names sell in the neighborhood of $150-250
Maybe a little less for one that contains z, x, q, j, etc...
Of course, usually lots more for one that has meaning
I've been watching them for the past year or so around a few forums....today I'm seeing them priced at a minimum of $60 on up...a year or so they were going 35-45...of course there are also many of them listed in the hundreds and thousands....