I'm not sure I've come across too many apps that were pure crap to begin with but I've seen several good applications jump the shark over the years.
Aldus Freehand. It used to be my favorite (with a bullet) vector drawing program (over Adobe Illustrator) but by the time it got into Macromedia's hands, it was a painfully slow bloated mess.
Adobe Premiere is another such. Actually, it just rotted on the vine while everybody else surpassed it.
Any version of Commotion after 2.1. It used to be AMAZING but rather than improve upon its painting tools to make it godlike, they tried to turn it into another After Effects and ruined it.
This is a chance for you to air out your frustrations about crappications that you use or have used. You may ask, what is a crappication? Well, kids, a crapplication is a piece of software that is sheer hell for you to use (Windows Me), it may constantly cause system issues, or just didn't work for you at all.