Nightfly is still Fagen's best release and pointed out it is the proper follow up to Aja. Gaucho is not my favorite.

I love the chord progression on New Frontier. Here is the video. It is on my all time favorite videos. I love when they showed Brubeck Time Out cover
http://www.youtube.com/watch?v=qBruAooXPNU

I liked the second half of his next release Kamakiriad

On The Dunes has the epic Aja feel to it and has a nice long coda
http://www.youtube.com/watch?v=eUbKaT0OPp4&feature=related

Tomorrows Girls is a nice video and song
http://www.metacafe.com/watch/wm-A10302B0000186391Y/donald_fagen_tomorrows_girls_official_music_video/

I couldn't find Teahouse On The Tracks which is also great

His next cd Morph The Cat is not too good. He seems stuck in a rut, stuck in a rut stuck in a rut (excuse the Monty Python sketch LOL) Only song that is good is the title song and it makes up for the rest of the cd being so so

http://www.youtube.com/watch?v=qgfi6pbW-BQ