I think x87 fpu is the only 'weird' floating point units left. I think if you stick with 64-bit double precision floats or 32-bit single precision floats, where the registers are also 64 or 32 bits, all the modern stuff behaves the same. x87 is just weird because registers are 80-bits ... the idea was to have more accurate results from more precision, but it ends up weird because if you run out of registers and have to spill to memory, you typically lose precision.

Edit: since this post was second chanced, I can add on that some of the pre-PC consoles have weird floats too. If they had floats at all. Lots of fun for emulation developers. Even fun for contemporaneous game developers... PilotWings on the SNES comes with different revision accelerator chips and the demo only works properly on the early revision chips (but I think? the later revision chips have more accurate math). The PS2 FPU has weirdness around NaN, Infinity, very large numbers, and denormalized numbers. Etc.

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