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I use it to make breakfast everyday.

eggs (tab) compose with (tab) stove (enter)
oj (tab) pour into (tab) cup (enter)

Seriously, I use it mainly as an app launcher. I don't like it to index my whole HD because it tends to slow things down a bit. I couldn't imagine using a mac without it.
 
I only really use it as an app launcher, but sometimes use it to send an email to someone in my address book, rather than opening mail and typing in the person's address.
 
I've tried it a few times, but I can never really get the hang of it. Spotlight, command-tab, and keyboard shortcuts just seem to work faster for me.
 
Mostly as an app launcher, but man is it ever handy. Also nice for launching a particular artist/album/song in iTunes.

Fn-Fn-i-M-o-v-Enter!
 
app launcher, file launcher, 1-touch disk image mounting and itunes play/pause... it's so great. I don't know how I used a mac for years without it...
 
App launcher + Keyboard Shortcuts (triggers)

I assign AppleScripts to triggers to do common tasks ...such as

Command+Shift+Up Arrow = Play/Pause iTunes
Command+Shift+Right Arrow = Next Track
Command+Shift+Left Arrow = Previous Track
Command+Shift+Down Arrow = Bring iTunes to front

Command+Shift+* = Upload the file to my home machine's desktop

etc.
 
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