(My coworkers are supportive, so I'm not being anti-social; I'm just trying to compensate for the space we have.)
Get some 1x2 or similar wood, in the lengths you need for the wall. Use a square to keep things...well...square. Measure twice, cut once, and assemble. Use a pneumatic stapler (and corner pieces) to keep it all together, or use angle brackets/braces and screws (if using screws, pre-drill holes). Once you have the frame done, string some steel wire between each edge (stringer), and top to bottom (perhaps weaving it) creating a open mesh with say 3x3 inch holes. Alternatively, get some hardware cloth of the same size (chicken wire would work well) and tack that in place. Then cover the center with some polyureathane foam, then cover with cloth. Add some right-angle "feet" to keep it standing.
Too much work? You could make something heavier using 3/8 plywood - face on both side with cork spray-glued on.
If that still sounds like too much work - and you have some money to throw around - look online (craigslist is a good place) to find a local used office furniture/supply company. Many of these places sell (some even install!) used cubicles and partitions. They might have something in your budget (sometimes, they sell these components dirt cheap compared to new - you wouldn't believe what a cubicle costs).