Best small, desktop speakers, $500 or under (new or used)

I own nht C1's and also kef q150s.  The nht's can be found less expensive than the link provided, just do a quick search.

I prefer the Kef's personally, but ymmv.

NHT and KEF -- really thinking about them.

@b_limo
http://www.hifi-classic.net/review/pinnacle-pn5-plus--452.html
$149 in 1986 = $350 today.
Of course, look at some ELAC speakers at the lower price points; many say these are doing a far better job than their peers. I don’t know what was said about Pinnacles at the time.
Also: some repairs. Woofer replaced on both; one from Pinnacle, the other from a Dayton audio woofer which fit. Tweeters original.

They are quite different. NHT are sealed, Kef are rear ported. Kef are quite a bit larger footprint. 
NHT are more forward sounding. Kef have more bass. 
NHT look nicer, nice piano black finish. Kef wood trim looks pretty cheap. 
But to me the Kef sound better playing from Bluesound Powernode 2.