I know John33 was thinking (upon request) of adding support for FLAC input in OggdropXPd. Don't know if that goes for LamedropXPd as well.
A few days ago I read that libsndfile (used in OggdropXPd among others) are working on FLAC input support, which might make it easy for John33 to implement FLAC support in his xxxxdropXPd utilities. Ask him for more info.
I'm eagerly waiting for this too
Edit: There is an easy way of doing this in Winamp by using FLAC input plugin and Lame output plugin. Then just hit the play button.