Cropping from an angled selection

For years I've been convinced that there must be an elegant and quick way to crop a photo after performing a transformation or canvas rotation, but for the life of me I can't figure out what it is. Does anyone know of a way to shave the excess out of a trapezoidal selection, without having to carefully line up four crop lines?

Thanks,

MB

What about using the crop tool itself to perform the rotation and crop all in one go?

There is a script on the Adobe Exchange which does this.

< http://www.adobe.com/cfusion/exchange/index.cfm?event=extens ionDetail&extid=1042987>

Chris and George,
Thank you both for you quick replies. You're right, Chris, that I could use the crop tool, and I often do. But, being a little on the retentive side, I often prefer to use options for which the controls are more manageable.
George, I had forgotten about that script, so thanks for reminding me. I loaded it a couple of years ago but couldn't get it to work, so I'll give it another try.
MB