Wednesday morning hit different for $NXDR holders - shares rocketed up 49% in early trading, marking the biggest single-day jump we've seen in over four years.

The catalyst? Eric Jackson, the activist investor who previously orchestrated that wild retail pump on Opendoor, just went long on this neighborhood social platform. Guy's got a track record of rallying retail money behind his plays, and looks like the market's betting he'll do it again.

That kind of move doesn't happen in a vacuum. When someone with Jackson's reputation publicly backs a name, especially one flying under most radars, day traders and momentum chasers pile in fast.