My friend gave me a cutting of this and called it an "Ice Plant" but I haven't been able to find anything similar in any book or web-site by that name. It was very easy to start - just stuck the cutting in potting soil and watered. It is doing well and has grown considerably on being watered once a week, so I'm just curious as to what it really is!
Hm... I don't know the english common plant names (unfortunately), but I think it's an Aptenia cordifolia...
I looked up the Aptenia cordifolia and didn't think it was the same plant at first because the description included "leaves up to 1 inch long and wide" and in the photos, the leaves look smaller. Some of the older leaves on my plant are over 2 inches long x about 1" wide. Then I found this photo: "Rock Rose" which looks nearly identical to mine. Thanks!