I have a problem reading social cues. When I took drama as an A-level college course, we had 'circle-talks' (not to be confused with circle-...). I tended to get overexcited and talk for five minutes at a time. Eventually the teacher trained me so that she put a hand on me (that is, my shoulder or something), I automatically added 'and I'll be quiet now.' and went totally silent.

This Troper(Jinxed Blackcat) ''so'' very much. It's practically a catchprase for me since whenever I do something particularly silly/ditzy I'll keep rambling trying to explain or cover my tracks and wind up trailing off going "aand I"m shutting up now."

This troper has a number of friends (and includes himself) who sometimes need to do this because they will try to justify something they said and will just keep making it worse. When someone else begins making digging motions or says "six feet, seven feet,..." it's the cue to invoke this trope.

This troper has a tendency to say "And... shutting up now. But really, I meant..." and not shut up. Apparently its quite annoying.

The dorm this male troper lived in as an undergrad played SuperSmashBrothers alot. He would often play Samus, as he usually preferred female characters in fighting games. Someone made a joke about how SamusIsAGirl (not that unusual). Not normally given to bantering, this troper was feeling bold and retorted "At least I'm secure in my masculinity to play as a girl." Except he didn't say "masculinity". Cue laughter, humiliation, and the trope.

This Troper has a habit of saying "Shutting up now", falling silent for about ten seconds, then starting up a conversation on a different subject. This always happens over dinner, as I don't speak enough at school to even constitute a minority in any argument.

This troper will usually say, "I'm going to stop talking now," when he realizes he's rambling about a subject his listeners do not understand. Also, though more rarely, "I'm gonna go over here..." and walking away is a form of this.

This troper has a few NoSocialSkills and Cloudcuckoolander tendencies, which lead to me doing several versions of this on a damn near daily basis.

A random outburst, involving stuff that other people wouldn't understand or care about, often ends with me quoting the trope.

This troper frequently finds himself ending sentences with variations on this (usually "I'll shut up now", "I'll be quiet now" or "I'll stop now"), or sometimes, more extremely, "I'll go away now".

This happens to me several times a day: #QUOTE#'''Me:''' *rambling* ...wait, I'm rambling, aren't I? #QUOTE#'''Other person:''' *nods* Uh-huh. #QUOTE#'''Me:''' Oh, okay. I'll stop now... So, anyway... *starts talking about something else*