I would like to hook up my Kenwood TS-2000 to my Mac Mini. What do I need??
Basically a real computer would really help a lot

Just kidding!
The "RigBlaster Plug-N-Play" (from West Mountain Radio) is what I use on my TS-2000 but it's on a PC. Basically on the computer side, for most commerical interfaces, you'll need either a physical RS232 or a "COMPATIBLE" USB to Serial adapter and soundcard I/O for RX audio in from the radio and TX audio out to the radio. Some of the newer interfaces use just a USB port and have an internal soundcard capability but I don't think they are compatible with a MAC.
Gene W5DQ
A rigblaster PNP should work out of the box with a Mac Mini, but if not you may need to install a driver for the UART:
http://www.silabs.com/products/mcu/Pages/USBtoUARTBridgeVCPDrivers.aspxI use it with Ubuntu running FLDigi, which is "available" for Macs, but might need to be compiled. Note that there's a native Linux driver for the CP2102 UART chip, so it just showed up as /dev/ttyUSB0 when I plugged it in. I know that OSX lists USB serial ports a little differently.
If you just want to access the TS-2000's TNC you'll just need a USB-serial adapter and whatever software you like.