This is why I like C# - inventive problem solving, rather than relying on the couple niceties already built in. Though I *might* have tried to use a magic value [e.g. nan] instead of boxing for performance reasons. Hmm... should benchmark that.
I know I'm going to cop some flack for that - and bring it on. But take a look at how things could be done vs how they are - and there's a lot of improvements that could be made. Creating US snippets but not C# snippets isn't a smart decision if you think about it.
Disclaimer: This isn't a deliberate choice on U3D's part [at least I hope not] - just an interesting turn of history.