Soft squishy feet

Can anybody recommend a small soft rubber footer? I have a couple of small components, which don't have footers, that I wish to stack, but I don't want a footer that will leave a mark on the top of the unit. I was thinking about Herbies, but I don't know if they will leave a mark.

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Herbie's don't leave a mark where I use them, and there is statement on website about being different sonically compared to sorbothane.
Herbie's seems to enable very detailed, and extended, clear sound. No single footer is "universal," but the unique ninety day return trial period should let you hear for your self.
Another vote for Herbie's footers. I use them under all AV electronics. They even noticably sharpened the picture from my DVD player.
Tenderfeet from Herbie's Audio Lab are excellent. 90 day Trial period and you are dealing w/a first-rate gentleman. (Steve) Very Highly Recommended.
I use the tenderfeet under a tube amp and I didn't hear a hint of difference in the sound. I will leave them of course for peace of mind, but I didn't hear a whole lot (if any difference) with them. Which may ultimately mean I need to further isolate.

Either way, shipping was fast, and overall great buying experience with Herbies.
Jc51373, it may also mean that you amp is very well designed and does not need any further isolation. On some equipment, isolation seems to make a difference, on others there is no or negligible difference.
Pubul, good point...I want to believe that is true, but the self-destructing audiophile in me always has to tweak and upgrade, and play with things. : )

Tonight I added sorbothane sheets (cut into small squares) with adhesive backing to all the edges of the shelving on my salamander rack. Again, not much of a difference, just small from my first listening session. It did however do a great job of reducing vibration in the shelf though, I can feel the difference when music is playing.
Ok, so the sorbothane under everything is a no go...I don't know if I can completely describe what it did. Everything felt darker, too dark. Voices sounded more distant, and the sound stage definitely shrank some.

So I pulled it out from the corners of the shelf where my preamp resides and it sounded immediately a little bit more back to the way it was. I think you need to be careful with this sorbothane stuff, it can really make a significant sonic difference in a system. Good or bad.

I am curious now, I pull it all out if it will sound even better. Good way to find a balance potentially.
I won a Salamander too. I bought solid maple wood (2") from TimberNation and use thise cork and rubber squares sold by MapleShade (I bought them froom an indsutrual supplier for about $2 a piece)and place the equipment direct on the maple shelves. The equipment looks great, the maple is very non-resonant and heavy, and the cork stuff seems to be a really good isolation material. Frankly, I don't know if it sounds better, but I did stop worrying about it (for now).
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I agree Tvad, so this was a learning experience for me without a doubt. I went with the notion that all tube equipment needed to be isolated, and that Sorbo was best for it. I was wrong.

I have since removed most of it and things are back to normal.
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