Just a little tip, as the syntax of less (less css) is so similar to css, just add a new file type in Netbeans > Tools > Options > Miscellaneous > Files like so:
Update: I found less editing works a lot better with Netbeans 6.5.1 than with 6.8. The code formatting of 6.8 is too picky and will essentially not format less as it’s not proper css. No such problems with Netbeans 6.5.1 which I also use on Windows as a vastly superior less and css editor compared with Visual Studio.
You can always get Netbeans 6.5.1 and other versions through this page:
http://www.netbeans.info/downloads/dev.php

November 7th, 2009 at 7:01 pm
Nice but the CSS colorator fail on some LESS syntax (display errors and dont understand variables, nested rules…)
November 11th, 2009 at 1:18 pm
@Damien: Thanks for your comment! You’re right, it’s definitely not perfect and will display plenty of errors on the side bar. But better than nothing I guess. It shouldn’t be too hard to make it right but I have zero experience hacking NB.
January 7th, 2011 at 10:44 am
There is now a lesscss module for netbeans.
Available from the plugins dialog in netbeans 6.9.1
Sources are here:
https://bitbucket.org/killermonk/lesscss-module
January 9th, 2011 at 4:54 pm
@Karsten: Thanks, very helpful this new plugin. As outlined in the post update I stayed with Netbeans 6.5.1 because it was unobtrusive with lesscsss and even did nice reformatting. A specialized plugin should be even better.
February 3rd, 2011 at 5:57 pm
Do not understand how do I download and install this plug-in for NB 6.8 Didn’t see any *.nbm files on BitBucket distro…..
P.S. I’m on Windows.
February 6th, 2011 at 10:02 am
Thanks, this is just what I was looking for when I was trying to work with less on netbeans for the first time. I’m currently using 6.9.1. If it is still too picky I think I’ll try the older version you specified.
April 30th, 2011 at 6:02 pm
working lesscss module (tested with netbeans 7.0)
http://services.netbeans.org/pluginportal-2.0/plugin/32782/lesscss-module