One of the killer features lacking in most scripting languages is the 
ability to "compile" or sufficiently "obfuscate" scripts so they can be 
distributed for execution without revealing the original source code.

Is this possible with Ruby today?  If not, is this something planned for 
future versions?  Are there 3rd party tools that do this?

There are many practical reasons why this feature is important. One 
pervasive example is where a small business hosts their website with an 
ISP that has the ability to access all the files/scripts.  The company 
might have scripts that contain database passwords or registration key 
algorithms  they don't want visible to non-employee system administrators.

If I'm not mistaken, this feature is so needed that there are commercial 
perl script obfuscation tools--people are literally willing to pay for 
this feature in Perl.

Having such a feature built-in with Ruby would be absolutely fantastic. 
  Perhaps the bytecode can be optionally generated in a manner that 
combats easy reverse engineering (just enough prevent automated reverse 
engineering since manual efforts are virtually impossible to prevent).