Hayashibara Megumi - Too famous.
Ueda Kana - First as Kohaku in Tsukihime, then Reika in Green Green, and I just found out she's also voiced Fukuzawa Yumi in Maria-sama ga Miteru
Toyoguchi Megumi - Voiced two of my favorite characters: Satou Sei in Marimite and Machida Ayaka in Stellvia.
Wakamoto Norio - Johnny in the 2D fighter game Guilty Gear, Chiyo-chan's dad in Azumanga Daiou.