The Los Angeles Rams made a huge splash during the offseason by signing linebacker Bobby Wagner as a free agent. That deal was apparently initiated by Wagner himself in a manner that convinced the organization itself that they were being pranked.
Wagner represented himself in contract negotiations, and reached out to Rams GM Les Snead, along with a number of other executives, to signal his interest in joining the organization. Snead was not even convinced that the message was real.
“I think he signed off as Bwagz, and I’m like, ‘OK, is this real?'” Snead said, via Gary Klein of the Los Angeles Times.

The Rams did their due diligence and found that the message was legitimate, which prompted them to register their interest and ultimately land the star linebacker.
The Rams’ case was probably helped by some in-house recruiting. Still, the linebacker’s unconventional free agent process seems to have worked out well for him.