There was a discussion about a similar card a couple of weeks ago. The Panasonic CF-V21P and the IBM 700 PS2 both used a similar card as a memory upgrade. The card in my Panasonic has two rows of 44 pins though and fits in a slot other than a PCMCIA. I believe the Fujitsu 510 tablet also used a memory card similar to yours and some early handheld or palm-sized computers may have as well. I've heard of a few cards that would fit in a PCMCIA slot but either the pinout or the voltage was different and could cause damage if inserted. Without some other identifying information it would be hard to determine what your card was designed to work with.
Before PCMCIA was a real standard, all kinds of cards were produced. For my Epson PX-16 I have an interface for a card like this. On the bottom side of the page (http://fjkraan.home.xs4all.nl/comp/px16/mel/) is the card compared to a 'normal' PCMCIA and a CompactFlash card. The Epson interface only works with Mitsubishi 60-Pin MEL-Cards.
Some of the older Toshiba laptops (old white ones of the 486 era anyway) used a card that looks a lot like that for RAM memory expansion...as did the HP LaserJet 5L/6L. Hard to say for sure what it was used for...