I can see where Jewel is coming from, but the whole point is people just enter into this for a bit of fun, which is all it's meant to be, but the underlying point is just trying to get people to dip a toe in the Photoshop waters. The silly things people have done here with pics are all involving simple techniques which have other serious and powerful uses which can drastically improve your pictures. That's the real message.
I'm sure Kenco wont mind me saying that a few short months ago he wouldn't have been able to submit his amusing contribution,, but he has done, and the fact he's getting into Photoshop is more and more evident with the quality of the shots he's posting here.
The simple techniques you see here can drastically improve your ability to turn out good work and sort out problems when they arise, but you gotsta get in there somewhere and get started.
Taking Matty's (EosD's) pic as an example, the mask he drew around the Citroen to cut it out of another picture, had so many other uses and could have been used to darken, lighten, desaturate, apply any number of filters to it, even change the colour of the car. And that's a basic technique to selectively deal with problem parts of your shots and a common problem that crops up here all the time.