LOPSA-East (and many conferences) have a session called "lightning-talks". This is where people do 5-minute talks. The talks range from technical to personal. It's invariably one of the most enjoyable sessions of the conference. You can generally sign up for a 5-minute slot usually right up until the session, though once the space is full it is full.
If you have something to say but have been intimidated by the prospect of putting together a 45-minute talk, going through the whole proproposal process, and so on, this is a great way to get your feet wet. The audience is highly receptive to new ideas and new speakers. You are among friends.
Lightning Talks coordinator Adam Moskowitz has put together a web page giving more details. Check it out!