Half-frame SLRs....

[Removed Account2]

I know of 2:

Olympus Pen (F / FT)
Konica Auto-reflex

Was there any more?

 

[Luc More]

Yes, but less classic models: the Yashica Samurai family (X3.0, X4.0, Z)

Fixed lens SLR with a zoom, autofocus, programmed exposure. The most weird form factor for a 35mm camera. Looks more like a video cam. Takes landscape oriented pictures in the normal position (actually makes it difficult to take portret orientation pictures). I have a Samurai Z and enjoy using it.