One of the most valuable features of Small Basic is the ability to extend and add features to the language, allowing you design and create beyond the limits of the vanilla options. The LitDev extension is a very popular example, it adds new methods to abstract common procedures as well as implementing more efficient alternatives to some vanilla methods. I recommend to anyone who is undertaking a larger project with SB to explore the LitDev extension.
What if you wanted to make your own extension?
In 2012 a small contest was held for best tech net article, and the first place prize went to Liam McSherry's article on extending Small Basic with C#, here is an excerpt from the introduction:
"Microsoft Small Basic, while a good language for a beginner, is rather limited once you really get into programming. If you feel you're rather advanced with Small Basic, but you also feel that you're being limited by it, you may want to write an extension. You may also wish to write an extension simply to help the Small Basic community by expanding what they have available to them.
To write an extension for Small Basic, you'll have to select a CLR-compatible language to write in. This tutorial will be using Microsoft C#, but there is a large selection 
of languages compatible with the CLR which can be used to write a Small Basic extension (and we have a tutorial for writing an extension in Visual Basic.NET here). This tutorial will assume that you have a grasp of using Visual Studio, which is the preferred environment for developing for the CLR. Microsoft Visual Studio 2012 Professional will be used in this tutorial. "
In addition you may want to check out Small Basic: How to Create an Extension Using VB.NET
I'd love to see some new extensions that the community can use to reach new places with Small Basic!
-jadamelio