For specific usages (individual point processing and interaction with other geometries) I'm using <a href="http://postgis.refractions.net/">Postgis</a>. However, I don't know of any way to directly load .las files.(GPL)<br>
<br>R (<a href="http://www.r-project.org/">http://www.r-project.org/</a>) is also a nice tool for particular processing however it doesn't hold lots of points at the same time and it's slower than C++ but you have access to a panoply of (statistical) tools. (copyleft)<br>
<br>That said, it's a nice question and I'm happy to learn about new tools !<br><br>Etienne<br>