Let's see, Prius gear/swag I've received from Toyota:
worldtime calculator (long wait for my Classic)
keychain (long wait for my Pioneer 2004)
stuff given to me by dealers (referrals, purchase through them, or I bought from them):
wristwatch in a plastic case
luggage tags
stuff I've seen but didn't get:
embroidered baseball cap
stuff I got at the Prius Engines of Change media tour:
cloth-covered notebook/binder
T-shirt
breath mints (makes your breath as clean as the Prius' emissions!)
magnetic name-tags
I'm certain that I'm forgetting some other swag somewhere...
I have heard of lunchbox coolers sent to some Classic Prius owners... There was another gift for the first Prius owners, but I don't remember what that was, but it was different than the calculator...)
(Classic Prius owners would get the calculator, and later a copy of the owner's manual, in the mail while waiting... So, when your car came in, you had 2 owner's manuals, but you already had time to read it through before you got your car...)
Off of eBay I did buy a Prius polo shirt, but that wasn't a Toyota item.
For a while, Toyota partnered with pixeltees.com to create priustees.com, where owners could make their own Prius shirts (use actual Toyota logos and graphics, besides uploading their own). I guess the contract ran out recently... I recall that there were several dozen designs made by various owners across the country that were available, besides whatever you created yourself.