This post is part of Mashable’s Spark of Genius series, which highlights a unique feature of startups. If you would like to have your startup considered for inclusion, please see the details here. The series is made possible by Microsoft BizSpark.

Name: CloudApp

Quick Pitch: “Share files fast with your Mac. The simplest, most effective way to share files.”

Genius Idea: CloudApp is a utility for Mac OS X 10.5 and higher that makes it super simple to upload files under 50MB to the cloud for easy sharing. Thanks to plugin support (called Raindrops) and easy hot-key assignments, you can literally upload files and folders of all kinds quickly and easily and then get the shortened URL location of the file copied to your clipboard to make sharing even simpler.

There are a lot of great services that make it easy to upload files and folders to the cloud — Dropbox is one of my personal favorites. Sometimes you just want to upload a file though — like a screenshot, folder or an MP3 to the web, and you want to quickly get a URL so that you can share that file with friends.

This is exactly what CloudApp does. You can either drag-and-drop files directly to the CloudApp menubar or you can assign a hotkey that will automatically upload selected files from Finder or files or images from other apps like iPhoto and Aperture.

Once the file is uploaded, the URL is copied to your clipboard. You can also configure CloudApp to automatically upload all any screenshot you take on your Mac — or file that you print to PDF directly to CloudApp.

CloudApp has an easy to use web interface that lets you access your uploads, delete them, and share the URLs with others. Linebreak S.L., the team behind CloudApp, is also working on an iPhone and iPad app, as well as a paid upgrade and custom URLs.

One feature of CloudApp that I particularly appreciate is that if you select a group of files or a folder for upload, CloudApp automatically zips that file group or folder upon upload. Then when you share the download URL with others, this is what they see:

CloudApp is simple, intuitive and extensible. Raindrops offer third parties a great way to integrate their own services or apps with CloudApp and you can download a number of Raindrops from the site. CloudApp uses Amazon S3 and Heroku to store files redundantly on multiple devices across multiple data centers.

CloudApp is free and while the client is only for Mac users, any user with a web browser can download files from the service. If you have a Mac and you’re looking for a dead-simple way to store and share files and folders, give CloudApp a shot!

Do you use any cloud-based services for sharing files and folders? Let us know!

Sponsored by Microsoft BizSpark

BizSpark is a startup program that gives you three-year access to the latest Microsoft development tools, as well as connecting you to a nationwide network of investors and incubators. There are no upfront costs, so if your business is privately owned, less than three years old, and generates less than U.S.$1 million in annual revenue, you can sign up today.

Entrepreneurs can take advantage of the Azure Services platform for their website hosting and storage needs. Microsoft recently announced the “new CloudApp()” contest – use the Azure Services Platform for hosting your .NET or PHP app, and you could be the lucky winner of a USD 5000* (please see website for official rules and guidelines).”

Reviews: Dropbox, PHP

Tags: apple, cloud computing, cloud storage, cloudapp, Dropbox, mac, mac os x, mac software