Ok, I'm a heavy metal fan but this takes the cake. OBACHAN METAL. ワロタ！

The "band" オバメタル・ライジング (Obametal Rising) is comprised of 3 women aged 40, 44, and 45 (it would have been funnier if they were really obachan aged like in their 60 and 70's). Here is their blog and some really shitty quality video clips.

炎のエコロジー (Fire of Ecology)

ゴッド・オブ・サンダー (Gods of Thunder)

And here is a "karaoke song" (it is just the name of the song but watch the clip...) video for the win

"I am the god (god!) OBASAN-DA".  ROTFLMAO. You rock ladies for having an awesome sense of humor. ＼m／（＾_＾）＼m／