Alfred 1 was pretty awesome. Even just as an app launcher, it was handy. You hit your hotkey, type a couple of characters, and that was all you needed. No mousing around, no trying to find the app in your crowded Applications folder. Just a couple of keystrokes.
Alfred got even better when you'd use other features like custom searches. We have some internal systems that can be driven by search; pretty soon, rather than having to open up a browser window, navigate to the right place, and search, I just type a few characters and search. Alfred takes care of the rest. You could easily extend it to search any search engine, the App Store, almost anything.
This was just scratching the surface of Alfred. I didn't really use features like the Clipboard/Snippet manager (which I'm trying to use more of) -- have stuff you always type or cut and paste? Add a snippet and you can quickly paste it into any app. There's a really nice file navigator, quick file mover, all sorts of powerful features.
But, again, even if you just used it as a quick app launcher, it was pretty handy.
Alfred 2 just came out.
It added a few features, but none more powerful than Workflows.
Workflows are sort of a "change the way you use your computer" feature.
Basically, you can wire up a keyword or key command, to applications, or scripts, or almost anything you can automate on your computer. And, these bits can pass data back and forth. It sounds mundane. Then you download a workflow from the Alfred Forum that sounds interesting, and your eyes get big and you think "huh, I bet there's lots of things I can do with this."
A great example is the Weather workflow. You type "forecast", and right inline, you see what the weather forecast is. No web browser, no need to open anything else, you just get what you want. I've got workflows to manage Spotify (start/stop/find an artist), show my current IP address, add stuff into OmniFocus, turn on a secure proxy (can't be too safe when you're web browsing out in public), automatically upload files to common place.
Anything you can think of, someone can probably put together a workflow to automate it.
It's a fantastic, game changing feature.
Alfred 2, the free version, is worth downloading. But do yourself a favor and buy the PowerPack. It's something like $25 and is completely worth it.