See, at any given time, Kismet and NetStumbler give a huuuuuuuuuuuuuuuuuuuuge list of access points. Considering how quickly WEP can be broken (under four minutes) I'd rather not use it.
As much as I hate to support Nintendo's ass-backwardness on the DS, I may just wind up having to get a WFC USB adapter. :/