I can't do without it - used my old MS natural for 7 years, and with the new rig, bought a new keyboard for it
. Once you use a MS natural for a bit, I think you never go back to the normal ones. Its really comfortable typing - and you can work on the comp for hours at a time with no strain.
The monitor is a viewsonic E90 19" that I bought used. Occupies a lot of desk space, but the colour rendition is very good.
My new rig is a C2D E4300 @ 3ghz (TR U90), 3GB DDR 2 800 (2 x 1GB G.Skill+2X512 PNY), PNY 7900GS, Xfi XtremeMusic and a Coolermaster extremepower 600W and a MS Natural 4000 keyboard..