Who uses the ExpressCard slot?

My 15” MacBook Pro contains an expansion slot. Called the ExpressCard/34, it’s the successor to the old PCMCIA slot (which, of course, means, “People Can’t Memorize Computer Industry Acronyms”).

According to the PCMCIA (okay, the Personal Computer Memory Card International Association), the ExpressCard standard is to “carry forward the benefits of ‘plug-in’ I/O cards to the generation of personal computer devices.” There are two type of ExpressCard devices, 54 and 34; the number indicates the width of card in millimeters.

In the old days, I used to put four types of cards into the PCMCIA slots on notebook PCs: Modem cards, Ethernet cards, WiFi cards, and carriers for digital film cards, such as CF and SD cards.

Today, I have no idea what to put into the ExpressCard/34 slot. My MacBook Pro, and most other modern notebooks, already contains built-in Ethernet and WiFi. The MacBook Pro doesn’t have a modem, but Apple sells one as a USB accessory, not an ExpressCard accessory. As far as I can tell, Apple doesn’t offer any ExpressCard accessories at all.

In searching around, I’ve found very few ExpressCard accessories on the market. Martin MC Brown, writing for ComputerWorld, discussed the Transcend solid state disc for the ExpressCard/34 slot, which could be used as a scratch disc. The SSD comes in three sizes, 8GB ($133), 16GB ($255) and 32GB ($499). It would be interesting to see if it’s bootable, and if so, could be used to replace a rotating hard drive.

Other than that, I haven’t found anything compelling beyond a few wireless and networking adapters, and of course digital-film readers. What’s your experience? Do you use any ExpressCard accessories with your notebook?