I've been in the habit lately of just cutting off a piece of linen and taping it up when I need a certain size. Haven't had the right panels available or something. Makes for a bit more work later gluing and mounting things, but its convenient when you want to get right to work.
I'm about to hand my computer off now to get a new smokin' fast (big?) hard drive installed. Lots of tech upgrades lately. Some unplanned too.