Note worthy Omni Directional Speakers..

You mean truly 360 degree dispersion speakers?

Not many of those below the $8k range. But, they are a few quasi-omni directional speakers with supposed good performance.

Decware(pic) has the RL-1.5 Radial Speaker - 92dB, 37Hz ~ 22kHz, 4 ~ 100 watts, Max SPL 110dB, $1,295. The RL-1.5 uses a 12" driver in omni-driectional mounting and a semi-directional tweeter. Check Decware's forum for some owner testimonials.

Of course, Ohm is the most famous for quasi-directional speakers. They haven't produced a true omni-directional speaker since their model "A" & "F" series a while ago.

ohm walsh micros, tall...

As a budget variant, the Duevel Planets. Or else, used Ohms or Shahinians (Arc, Compass, Obelisk. Everything else I can think of is more expensive even used (German Physiks, MBL, the larger Shahinians, larger Duevels).
Regards,
Florian Hassel

MicroWalsh Talls - not true omni, but easier to place. The Duevel Planets look hip...

The best way to tell is, for $100 buy a full set of five, the Mirage omni's. Go to Parts Express and type in 'Spherex. where you will find a close out. Google the Spherex and you will find some hi-end reviews of these units. I have the original Sppherex xbox system. Unbelievable! You could also only buy two for $40. How can you lose?