Here is a nice alternative to the ProTools MBox series. Check it out.
Excellent choices for mobile musicians, sound designers, and podcasters, the USB 2.0 bus-powered AudioBox iOne and iTwo provide high-quality audio I/O for Mac®, PC, and Apple iPad®. These compact, ruggedly built interfaces offer high-performance Class A mic preamplifiers, record 24-bit audio at up to 96 kHz, and include powerful, easy-to-use Studio One® Artist DAW for Mac and Windows and Capture™ Duo recording software for iPad.
PreSonus | AudioBox i Series