Well impressed with this: http://www.flickr.com/photos/rockartwolfy/1313038988/
Is that a Scottish bullaun? And are there more of same?
Yeah it certainly looks the part, i have seen a few on my travels, mainly in Galloway..
such as..
Milnmark Hill, http://rockartuk.fotopic.net/c955715.html
or
Torrs http://rockartuk.fotopic.net/c1119236.html
It's certainly quite large for a "cup", perhaps 8" across.
Dunno about how many others there are ....
http://www.rcahms.gov.uk/pls/portal/newcanmore.details_gis?inumlink=39564