I haven't even shared this with Matt yet, but I was given a few sets of the feet that BEL ( Brown Labs) used back in the day. Just inexpensive and simple hard rubber feet. I installed them under my Ayre integrated as well as the Ayre QX5/20 and my Steven Nugent built Mac mini with Paul Hynes LPS.
Each piece sounded a bit better. Cleaner, tighter bass and a spec more stable soundstage. Not huge differences, but positive ones. These are a dirt cheap option for folks who have folded cases and don't have much money to play with. I think that Timbre Audio in Houston, TX sells them.
Get in touch with Joe Heusi or his son Michael if you want to get a set. They are really cool guys with a brand new, built from scratch show room. (713) 523-0494.
They have the Linn gear too. Matt, have you had the LINN in? I just realized that they have been left out and I know they do great digital. I have their lifestyle Kiko unit in the bedroom. It's decent for what it is, but their big gear is really good stuff.