Does anyone run 2 or more turntables...

Just to keep your thread alive, I now have 5 turntables up and running, although only 4 of them get even occasional use.  My Victor TT101, mentioned above, was finally fixed by a genius in NYC, JP Jones.  If you have a "broken" direct-drive turntable, JP can fix it. So, in my basement system, I use a highly modified Lenco with Dynavector DV505 and the TT101 with FR64S tonearm.  Upstairs, I use a Technics SP10 Mk3 (Reed tonearm) and Kenwood L07D with its built-on L07J tonearm.  My Denon DP80 is up there too, just sitting. I had promised myself I would sell the Denon if the TT101 ever got fixed, but I don't feel that urge any longer.  The market value of the DP80 is too low to make me feel compelled to part with it.

Does anyone run 2 or more turntables at the same time? What is your purpose?

Sure, I have two.  Besides just being fun, here are the practical reasons...
* One is manual and the other is a semi-auto.  The advantage of a semi-auto are obviously when is one is doing something else while listening.
* One is belt driven and one direct drive.
* One is modern and one is vintage.
* The above two points helps me avoid two classic debates in the world of vinyl because I don't have to take sides.
* Having two allows for two entirely different cartridges and both sound different.
* And back to my opening statement - its just more fun!

Two tables here. One for mono, one for stereo. If my stereo table allowed two arms I would have one table two arms.

A Luxman PD444 with three arms(2x SME 3012R + Kuzma 4P at the moment.) Unfortunately there is no space remaining to set up my three other turntables simultaneously. Multiple tonearms on one TT help in making close comparisons between tonearms and cartridges. They take a significant variable out of the equation. I can’t understand why more pro reviewers don’t have this arrangement. It can also help convince one how specious judgments of better/best can be in audio. A multi-arm setup convinces that above a certain level of performance, choices are largely matters of taste and are often price-independent.

Dave, It's telling for me to learn that you prefer the PD444 (direct-drive) vs your other 3 turntables, which if memory serves are either belt-drive or rim-drive types (do you have a Terminator Salvation?).  I have come to the same conclusion, as is obvious.  Does the PD444 use a coreless motor?  I have developed a preference for the sound of those that do.