My boyfriend ordered some 10x salvia extract from iamshaman.com and we did it with some friends in a basement. It was pretty intense - we all saw crazy visuals. It was like we were in a completely different dimension. We also found we felt like we were being pushed back by some sort of force. It can make you a little emotional too, and I felt really warm too.

Then my boyfriend got some 20x salvia extract and we did that outside. It was crazy! I had the most insane visuals. I've done shrooms, but I have yet to try acid, and I don't find I visualize a whole lot on shrooms - but the salvia was crazy. The stars in the sky were moving all around and things were not what they seemed to be. I got the feeling warm sensation again and me and my boyfriend got in an argument, but after it wore off we realized it was just because we got emotional from the drug.

In both experiences it only lasted about 1-3 mins. So it's very short lived.
What he ordered was the salvia extract both times because we smoked about 4 grams of the leaves and it did nothing. The extract can be expensive but it's worth it.

If you plan on trying it you must get a butane lighter because a regular lighter won't make it hot enough to work and you have to smoke it from a pipe (a joint won't keep it lit hot enough), but it only takes one hit to trip anyway. When we tried it we were told to hold hold the smoke in for thirty seconds after you take a hit, I don't know if that's necessary but we did everytime and our trips were really intense.

I'm not sure what kind of damage salvia does. All I know is that it is perfectly legal! So go to it!