koding.com has a free VM running Ubuntu. The specs are pretty good, 1 gig memory for example. They have a terminal online you can access through their website, or use SSH. The VM will go to sleep approximately 20 minutes after you log out. The reason is to discourage users from running live production code on the VM. The VM resides behind a proxy. Running web servers that only speak HTTP (port 80) should work just fine, but I think you'll get into a lot of trouble whenever you want to work directly with other ports. Many mind-like alternatives offer similar setups. Good luck!

Hostinger gives you the chance to build a project the way you want it. Our VPS hosting allows the use of multiple kernels and offers of a wide range of operating systems ready to install in 1-click. Simple, but powerful management tools will let you maximize the potential of your Virtual Private Server. Serious Hardware, serious Linux Optimization and a team of experts maintaining it around the clock.
Do you plan to sell products or services? If so, you'll want to invest in a web hosting service that offers Secure Sockets Layer (SSL). An SSL connection encrypts the financial information that shuttles between users' web browsers and your website, thus safeguarding the transmission of the purchasing information. Some hosting companies include a free SSL certificate when you sign up for a web hosting plan, while others charge close to $100. You can save some money by shopping around for services that offer the cheaper SSL plans.
Another way you can customize your VPS to your specific needs is with your choice of Linux operating systems. Select from the best versions of Ubuntu, CentOS, Fedora, Debian, Gentoo or Slackware. If you're in the middle of a project and want change to a different version or a different OS entirely, you can change and re-load your operating system on demand whenever you want!
A virtual server and a dedicated server differ by the number of users that possess resources on a physical server. With a virtual private server, some of the resources are isolated for individual users, but there are multiple users on the same physical server. With a dedicated server, a single user has access to all of the resources of a physical server.

It provides you with even more options, including root access, access to Apache and PHP.ini (modification of PHP variables), and much more. You can also install an SSL certificate, and all software program types. In short, you get more freedom in terms of administering and configuring your server, without the hassle of managing any physical hardware.