They're few and far between now days. I did play a 3 reel $0.25 machine at Cosmo on my last trip. If you come in from the strip and start walking past the blackjack tables there were a few banks of $0.25 and $1 3 reel slots on the right hand side, in the midst of a bunch of video slots.
do you mean reel slots, or videos slots? I think you can still find a bunch of $0.01 machines that let you bet $0.25- $0.50...but I 'm not sure that's what you are asking.
Even downtown 50 cent slots are a rare breed now. Still a good variety of 25cents though throughout all of DT, especially upstairs at the D.
KA Theater entrance doesnt have many slots near it anymore, mainly pennys now. Near the MGM buffet there are two large sections of slots and there are quite a few 25 cent machines there