Another well-known actor in the Cloud ecosystem is Google Mail . Such software doesn't require installation; you access it with a standard browser using a secure HTTP transporter on the Internet. You can create a new Gmail address using a fully automated subscription process. Such services are called Software as a Service (SaaS) since they provide a fully running product, with some options to customize them, but are focused on a specific use case. You can customize Gmail's style for your company and set some default filters for all the users, but you can't convert Gmail into a CMS—it's a mailbox service, period.

SaaS is based on another standardization: web-based applications that run on modern, JavaScript-powered browsers. They can compare with the installed applications for user experience (at least, for those of us who don't run Internet Explorer), but don't suffer the same installation and maintenance overweight. SaaS users need not worry about installation of security fixes, backups, and maintenance.

If the project you're working on matches with SaaS offer, don't look any further; just use it. The time that you'll gain can be invested in lots of useful things to make your business successful. If your business is successful, and you really hit a technical limit, you will be able to switch to a custom solution, but don't try to implement your own general-purpose service if you don't have highly specialized requirements. Gmail users would never consider writing their own mailing system.

The drawback of SaaS is that you have limited options to customize the software. They all expose API so that you can programmatically interact with the service to integrate with the third-party tools and extend it to your own need, but you can't change the general service spirit.