Thanks for the introduction Rick...
Tool is currently my favourite ear candy. Their songs are very organic (to the point of decomposing
) and textured, the musicianship is top-notch, Maynard has the best voice in rock right now, his lyrics are provocative, and the music makes you "feel". Although they have many progressive elements (they claim to be heavily influenced by King Crimson and Rush) including dizzying time changes, they don't feel right for AM. I think they are too dark and heavy for what AM has grown into.
For any adventurous souls who want to try them out, you should start with Lateralus. If you do try them, I'd love to hear what you think.