Best Flash Card for GBA/NDS?

[bcass]

I'm looking for a GBA flash card that does not need a battery in order for saves to work. I'm not talking about snapshot-style saves, I'm talking about when a game actually has a save function. It also needs to be compatible with an original fat NDS (slot 2 with nothing poking out), and ideally, at least 2 Giga Bytes of storage capacity (using either a micro or a mini SD card).