[Saxologist]

I think there should be a shop where you can trade in your girlfriend on a rating bases. They get a form much like this:

Attactiveness /10
Loyalty /10
Honestly /10
No of children /10
Skills in bed /10
Boob size /10
Friendliness /10
Dress size /20

Now, an independant judge would rate your GF, tag them, and then you will get points, which you could exchange for another lass or collect them to win some DVD's, CD's etc.

Obviously, amount of children would be lowest is best.
Dress size would be actual dress size.

This enables people not simply walking up to a fat bird in the street and getting traded in for a hot lass, with 5 kids (adds negative points) and extremely disloyal.


Foolproof.