I’m a relative newcomer to Macs, but one app that has quickly proven indispensable is Fluid. Designed to make dedicated apps for everyday tools like webmail—I use it to keep my Gmail account open in its own window—it uses site-specific browsers to keep things tidy.

Why not just use a new tab, you say? With Fluid, I can have one Gmail account open in my newly-created Gmail app and a second open in my usual Chrome tabs without any of the annoying overlap (logout mishaps, etc) that often crop up when using Google’s multiple sign-in feature.

Why, then, not just use a new window, you say? Here is where Fluid really shines—the app is so well integrated into the Mac system that using it creates an actual, dockable, app. Essentially, it has let me replace the default Mail app on my MBP with a Fluid-created Gmail app that gives me all the functionality I’m used to, all while keeping it within the interface I’m used to using online. An added bonus? The dock icon gets badged when new mail arrives.

Of course, you can use it for anything: Facebook, Twitter, YouTube; the list is as long as your bookmarks. Follow the link above to the Fluid site, where it is available in both Free and Premium versions.

(By the way, one of the reasons Fluid is so well integrated into the Mac system is that it was developed by Todd Ditchendorf—a former Apple employee who worked on Dashboard Widgets for Mac OS X.)