Serve up your videos via HTTP. Every Flash-based player supports that, and so do all mobile devices that use the HTML5 <video>
tag. You may lose some functionality versus RTMP, such as seeking to parts of a video that have not been downloaded yet. You should encode into H.264 to support the most devices (both Flash players and most mobiles will play that via the HTML5 video tag), possibly adding a WebM version as a fallback for Firefox users without Flash.
See Kaltura as an example of an open-source video player that automatically works with Flash or HTML5 depending on the device's capabilities. All you do is put <video>
tags in your pages and include the player JavaScript.
All CDNs support serving any content via HTTP, so this should just work with VPS.net.