(almost the) most-used app on my mac
Being that this is a utility app…I cant really call it "my favorite" or anything - but its pretty much perfect for what it does. I use it when I pay bills, I use it when I need to calculate something…and its definitely my most-used app (ok, minus the web browser and ical). I love how it fades itself - but the numbers stay visible, so when Im calculating and then updating a spreadsheet, I can still see it, right there on top. Kudos to the developers for the constant updates and improvements.
YLC about
Handy Calculator