Yes, for my mp3 player and portable speaker. I do believe it's far cheaper than having to buy new batteries all the time.

I use Energizer's Value Charger (their cheapest), the one that charges batteries for 8-10 hours. It can charge both AA and AAA batteries at the same time, yun nga lang you still have to wait half a day for it to finish charging. But efficiency-wise, wala akong problema. I just bought an extra set of batteries para habang naka-charge yung isa, may nagagamit pa rin ako.

They (Energizer) do have this super charger than fully charges your batteries in only 15 minutes flat, but it costs around P3K. Tsaka na lang pag mayaman na'ko.