When I make tea, I want to start drinking it right away, so I add ice cubes after steeping to bring it down to drinking temperature right away. This ThermMax tumbler maintains that temperature for a ridiculously long time. I have one of these for home and one for the office. I usually take one of them with me on overnight business trips. If I ever get wind that Thermos is discontinuing it, I'll start an internet campaign to bring it back into production—after I buy what remaining stock I can get my hands on. I love this tumbler.☒
You've seen what I do with it, you've heard how Merlin Mann uses it, and you've heard about it on the Mac Power Users podcast. If you don't have it, you're really missing out. The text substitution part is nice, especially now that snippets can have fill-in-the-blank fields that you can fill in on the fly, but the real power comes when make snippets that run AppleScripts or shell/Perl/Python/Ruby scripts. That's where TextExpander tips from powerful to magical.
I still have a “real” calculator in a drawer of my desk, but its batteries are dead and I have no intention of replacing them. This is my calculator—always in my pocket, always ready to go. All the functions you'd expect on a scientific calculator, plus unit conversions (including conversions you define) and constants (including constants you define). And now it's programmable, too. But despite all these features, PCalc's real strength is in its design, the little affordances that don't appear in a checklist but make working with it a pleasure.