I'd say the Roland MC-202 / SH-101 are very cool and not crazy expensive yet. I'm jonzing for a Roland MC-202 / TR-606 combo myself. I use a computer with Reason 3, Live 5 (battery, pluggo), and Logic. I also have a MM and MD for Elektron. My next will be a bent Speak and Spell / Read / Math. Then a Sidstation. I guess typical stuff for this forum. if I were you, I'd check out nanoloop at
www.nanoloop.de or a Yamaha CS01 for real cheap deals.