Two games I had never heard of previous to MAME, but are now on constant rotation..
Great Swordsman
I'm a fencer, so when it comes to finding any videogames depicting my sport, I'm only limited to either Soul Calibur II-IV, Bushido Blade, or Track & Field II. But when I found this unknown gem, I was hooked!
It isn't anywhere near technical enough, (of course, it's kind of hard to get remises, counter-parries, and balestras down pat in an 8-bit game,) but it's charming in that it's pacing is dead on, there is an incredible amount of emphasis on strategy and timing, and once you finish with the western fencing segment, you're presented with the eastern style of kendo. A very highly recommended title to try at least once, or more if you're a fencer and/or interested in the art of the sword!
Battle K Road
When I first played this game, I thought the emulation was busted. It was so slow, I had flashbacks of falling asleep while playing the original Street Fighter II on my SNES.. But I gave it a chance, and now I love it. Just as Great Swordsman was for the sport of fencing, Battle K Road is less Street Fighter, and more honest to the sport of martial arts, (aside from the karate bear, of course..)
It's slow gameplay gives you the chance to think and anticipate your opponent's attack and act accordingly. There aren't really any combos, aside from a few one-two jab-strike sequences, so you're only chance of making it past the first 3 opponents is to think ahead of your opponent and actually out-fight them. Best two of three format, with mid-round knockdowns carry the flow of the matches nicely. If you can get past the slow pacing of the fighting engine, you'll find a great fighter from Psikyo..