I had an idea today when navigating around in the shell. All my work related files are stored in <code>~/Work</code>. Under that there's a folder for each project. Sometimes there are multiple variations on a project or project with a similar prefix such as:
<ul>
	<li>radiopaedia</li>
	<li>radiopaedia-stable</li>
	<li>radiant-sites</li>
</ul>

When I type <code>rad [Tab]</code> in my shell (<a href="http://www.zsh.org/">zsh</a>) it kindly completes this to <code>radi</code> and gives a list of the other completions since there are several to choose from. I though it would be nice if the shell could learn from the choices I make. So if I generally choose radiopaedia then <code>rad [Tab]</code> would complete to radiopaedia but still show the list of option. 

I'm sure there are several other areas where an adaptive shell that learnt from usage patterns could be applied.