We all remember the first cell phone we ever saw. Riding the heels of the chunky portable phone (for use indoors) and the car phone, early cell phones were over sized, hyped and largely ineffective but still utterly captivating. It's hard to believe, but this month marks the 20th anniversary of an agreement 15 phone firms signed to build mobile networks based on the Global System for Mobile (GSM) Communications.

The BBC recently took a look at how far the GSM technology has come since 1987, reporting that there are more than 2.5 billion accounts that use this mobile phone technology today.

What's the future of GSM? While we look at most geek apparel with built in technology with some skepticism, experts say GSM tech will eventually be used in "the fabric of your clothing, your shoes, in appliances, in your car." They also predict it could someday allow people wearing monitors to gather and transmit information about their vital signs. It may sound wild, but consider how far we've already come.

Photo from the spring 2007 Willcom catalog.