2 DAWs but only one pair of studio monitors!

[Dowski]

Is there any type of relatively high quality but fairly cheap (say under $300) contraption I can use to switch between the outputs of two DAW's (one G4, one Mac Pro). Looking for something to save me the time, effort of having to reconnect the outs everytime I want to work on a diffent computer. I'm seeing stuff for $500+ but I'm hoping somebody knows of a cheaper alternative...any suggestions? Could be totally obvious but I'm stumped...

BTW, the new Mac Pro (2.8 GHZ quad core x 2) seems to be running 7.4 pretty well... only a few tweeks here and there
Thx

[Slim Shady]

Mackie Big Knob.

[Dowski]

Ah yes, forgot about that one!
Thanks!

[4string]

For the budget minded there is the Samson C-Control.

And I think (dare I mention the name here?) Behringer even has something similar.