When someone has their instant messenger set to invisible but yet is actively messaging, they are said to be on the instant messenger down-low
I was looking for a friend online and noticed he wasn't signed on, but when I sent him a message, he responded. He's totally on the IMDL.
A morbidly obese mid-western man or woman who wears inappropriate clothing for their size
I can't believe I can see the thong on that Indiana hipster through her tight yoga pants