The bare breast to bare chest is pretty common, and quite enjoyable. It's especially nice because it's always the dancer that initiates it. You get the feeling that she just can't keep her hands off you and wants you so bad she's unbuttoning your shirt and lifting up the t-shirt just to touch your bare chest...
One of the most memorable instance was during my one and only two-dancer-at-once dance I had several years ago. The dance was amazing, and the visual of having two hot (well, one hot and one ok) girls on my lap, and kissing each other, was increddible. They started getting into it, and including me in their fun, when the hotter of the two unbuttoned my shirt, and lifted my t-shirt. They both rubbed their breasts all over my chest, then they apparently tired of holding up my t-shirt because it was getting in the way. The hot one, Madison (some of you HHers might remember her from about 6 or 7 years ago) then ripped my t-shirt at the neck, and tore it completely down the front. Things got a bit crazy after that with tongues and lips and teeth all over my chest, nipples, neck... What a memory.
I left "The Wall" looking like I'd been mauled by a lion (well, two horny tigresses), with my shirt unbuttoned and untucked, the t-shirt hanging in shreds, belt askew, hair disheveled.. But that was okay, as bad as I looked, I could see the jealousy in the other patrons and I strode right out the door.
My wife was suspicious as to why my t-shirt was missing when I got home. Hmmmm....