Correct answers:
WTF1 - Hollywood fantasy film car from 1933 (Joćo)
WTF2 - for driving through minefields (metalshapes)
WTF3 - mobile stable from 1924 (75america)
WTF4 - Sandman's vehicle in Logan's Run (Allemano)
WTF5 - a dog-powered treadmill vehicle (guido66)
WTF6 - work of art at Vancouver Museum (Allemano)
WTF7 - for painting road marking lines (guido66)
WTF8 - airplane engine testing vehicle (guido66)