Reaper is a fairly new, inexpensive DAW. Not quite as pro as PT LE yet but gaining ground quickly. You can dload a demo with full funcionality, just a nag screen until you buy. One big advantage is it runs VSTs. Combine that with ReWire functionality, and it makes a great team member with PT, especially if you do a lot of MIDI stuff. I'm pretty sure it allows any rational grid, and even some irrational ones.