I have both parallel and USB style MIDI boxes for laptops and I really like the USB version - self-powered (it gets power from the laptop PC so you don't have to worry about missing wall wart), small (about one third the size of the parallel one - both 2 MIDI in and 2 MIDI outs versions). With a simple USB hub, you can use several other USB equipment simultaneously (like mouse, scanner ... etc). You can install USB driver and have the equipment up and running without rebooting your laptop. No more fiddling with IRQs and I/O addresses. An example of such device is the Midiman USB MIDISport 2x2 for Windows 98 and Windows 95 OSR2 with USB support. Price is under US$100. The PCMCIA type MIDI connection requires some sort of dongle(s) that easily break(s) over time. Usually laptops have only 2 type 2 PCMCIA slots - good for modem and network connections - you don't want to waste a valuable PCMCIA slot by dedicating one for MIDI connections, not to mention those PCMCIA-based MIDI devices are usually more expensive than the USB ones.