I had difficulty locating my watch the other day, and was trying to come up with something close to Tabata but doable without a watch, and one idea I came up with was taking your normal score, say 18, and adding 5 to it, and doing eight sets of that, with a 10 second rest. Normally, you can hammer the first few sets, but it catches up with you. In this scenario, you keep the reps the same, but the work interval would increase. However, you keep the rest interval the same. You count to 10, then go again. Just do them as fast as you can. If that doesn't give you a good lactic acid burn, I don't know what would.
Is it good? Hell if I know. Keep doing it. See what happens. Cain't hurt nothin'.