EBay

eBay is an online auction platform in the Movie continuity family and (incidentally) in the real world.

If you're a young teenager looking to score some cash to pay for your first car by hawking your great-great-grandfather's junk, eBay is a good place to do it.

Unfortunately, killer alien monster robots can also use it to track you down.

In the real world, eBay can be a good place to buy both new and used Transformers toys and other merchandise for decent prices. Less experienced buyers should beware, though, since scalpers also use eBay as a platform to make a profit, and their offerings are never good deals. In addition, ~~stolen~~ ~~leaked~~ prototypes "acquired through unauthorized means" also often end up being offered on eBay, often going for even higher prices than toys sold by scalpers.

Trivia

In the movie, Barricade states the eBay item number for Ladiesman217's glasses as "21153", a five digit number. In the real world, eBay item numbers had already reached the eight digit region by 1998; and in 2007, when the movie came out, they were already in the 12 digit region.
In issue 1 of the movie's comic book adaption, the eBay logo on Sam's computer has been changed into "ePay", possibly to avoid accusations of product placement.