I got a 4x6 black doormat from Home Depot for $20. It’s deep enough to keep my pedals and bass drum on the rug and nothing moves on a gig and because of the heavy rubber on the bottom, I can vacuum it to keep it clean. $20.
Since becoming pretentious beyond my abilities I've developed a hankering for a Persian style rug.
After searching for a 2nd hand one for a few weeks and finding the ones I liked were always the wrong price or the wrong size - I was amazed to find new for only £40 INCLUDING delivery.
Some lovely traditional patterns - I got this one. Great quality too, IMO.
'The Rugs Outlet' (UK)