I'd rate the EF 50mm f/1.0 as more exotic than the 50mm f/0.95 TV lens as other people still make lenses similar to the latter. Kinda wondering if I should have got a used f/1.0 when one popped up in the past, but decided if I ever wanted to go that route I'd take the speed hit and get the more modern f/1.2 so you have any resolution at all wide open.
I think there is a certain desire for what's no longer available. Some day I hope Canon remake the 1200mm as I'd like one. New.
If that doesn't get me me enough terrestrial reach with AF nothing will...
The MP-E65 is kinda unique as a 1st party lens these days I guess, but I believe Minolta used to do something similar.
For something else that is still made, I really like the fisheye zoom if only I need one enough to pay for it! And I still think tilt-shifts are kinda weird and funny, like they're broken and droopy.