how hot can it get?

[claymore]

We know that there is an absolute zero, but at the other end of the scale is there an absolute hot?

[jake-the-peg]

This is quite a crude way of thinking about it but temperature comes from the motion of atoms and molecules in a substance.

If you could get them to be absolutely stationary then you would have absolute zero.

There's no real sensible maximum, you can say that possibly it's the temperature where the gas particles are travelling at the speed of light and some theoretical models will say 140000000000000000000000000000000 degrees but that's rather speculative

You have also to cosider what counts, after all at these temperatures you don't have a gas or even really a plasma but rather a mass of subatomic particles with pretty much no interaction betwenn themselves contained in some manner .

At high levels we don't talk about temperature partly for this reason but rather about the energy.

CERN is shortly to start the LHC experiment which will produce Energies of over 1000 TeV or about 100000000000000000000 degrees by my calculations

http://www.wisegeek.com/what-is-the-highest-po ssible-temperature.htm

[Golf38]

I suppose the suns pretty hot - absolutely!