I like to practice guitar while standing up.
I found my knees were getting sore from standing on my laminate floor. I went to buy an anti-fatigue mat like they use in industrial plants. The cost for a 3X5 was $206.00 plus taxes. I can buy some serious studio equipment for that price.
I made an anti-fatigue mat for around $10.00 and it was really easy. I purchased interlocking foam mats. I then put a piece of left over carpet on top of it. A total cost savings of $196.00 and my knees do not bother me at all when practicing guitar.
|DIY Anti-Fatigue Mat|
The bottom (grey) is two pieces of interlocking foam. The carpet (beige) is a left over piece from when we had carpet installed a few years ago. I cut the carpet to size with a carpet cutter. Carpet stores will also sell squares for ~$5.00 a square if you do not have any old pieces at your disposal.