I've got the funky one:
I got a spare set of rubber seat grommets (to grip the main rail) from (what used to be whytoole).


In the bike picture the grommets were a touch too short for my bike, so I used very thin washers as spacers. The set-screws used for the grommets aren't really necessary if you add enough tension on the skewer. I'm a big guy and haven't broken parts yet, so I don't think the set screws are a real issue. In the seat picture there is a chicken-ring on the grommet, then 3 washers, then the bracket.

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On a shortish piece of 1x6 I mounted some short right-angle brackets spaced to hold the grommets onto the main rail, using some front wheel skewers for tension. I set the distance between the right-angle brackets to the same as the seat base in the picture. The marks on the board are for centering the brackets.
This is the front set. You can't see the other set in the picture, but they're mounted about 8 inches back, just far enough to let me put the seat all the way to the rear.
Onto the board I bungeed a standard basket. This arrangement works to carry things, act as a bungee rail and mud-flap. But, since I have the older style SACHS hub I use with a BOB trailer and don't keep it on. I still use it occasionally for extra capacity or when the trailer is too much.
Feel free to use this information to create your own bracket. If you have some innovation that helps the cause, let everyone know at the Yahoo! Groups BikeE and Bike E Forever! places.