Hosting Vaadin applications
Java servlet hosting is not as widespread as for instance PHP -hosting, and usually a bit more expensive for basic 'webhotel' -type services. This is not a problem when your project is getting serious, but for small personal projects and quick hosting of prototypes this might be an issue.
When your project is getting serious, you'll probably want to get your own dedicated (virtual) server. Amazon EC2 is for instance definitely worth looking at, but there are many other possibilities.
Below is a list of cheap services that have been tried to work with some Vaadin application. This does not necessarily mean the service is particularly good, but it might be enough for basic needs. YMMV. Most offer more expensive plans as well, but the main goal here is to identify cheap options. Feel free to add more: