By abnormal, I mean, not in the usual SUV (for Baja), coupe, hatchback or sedan forms. I'd allow exotics if you don't normally see them in a rally guise (i.e. Top Gear Bentley Conti GT).

Personally, I'd like to rally a Toyota Previa 4WD (rally prepped of course! unless I want to do barrel rolls). FMR Layout. Four wheels on the ground. 5-speed manual. 8 Seats. The title of the ultimate minivan hoon machine.

Oh and it's pretty damn cheap

Here's some other less usual ones

Subaru WRX (obligatory)

Targa Brick

Mitsubishi Delica Rally Van

The answer to everything with it's roof off

the way kinja formats stuff is making me cry :(