I had a SecurID card for using my laptop to connect to the company network at my previous job. You would enter a PIN, and it would give you a login code. There was a repeating countdown on the card, and when it hit 0, the code was no longer good. (I think this was 5-4-3-2-1 tick marks, but I don't remember for sure). Each repetition of the countdown took maybe 30 seconds (maybe less), so if it was low, you'd wait for it to start the next cycle before entering your PIN.

I think if you entered your PIN twice during a single cycle, you'd get two different codes, but the second code wouldn't work. I can't remember for sure, though. The card was the size of a credit card, only about 3 times as thick. The card did of course have a battery, but I had it for 2-3 years, and the battery didn't die in that time span.

Edit - forgot to mention: appropriately enough for this forum, that previous job was at Nokia.