Bryan here. Developer of Less.app.
I highly recommend AGAINST using the older version of LESS (the Ruby-based one). Less.js isn't just a javascript port of LESS, it's a ground-up rewrite that improves a ton of stuff, adds support for things that the old Ruby version doesn't have, and increases compiler speed by about 84%.
Rather than install the Ruby gem, install Node.js and run Less.js through Node from the command line. You'll still have all the -watch functionality, but you'll be using Less.js to do it, which means your life will be much better.
Alternately, use Less.js as a script in the website you're creating. This will work for development. When you're done coding, simply copy the CSS that Less.js generates (from your browser's inspector) and place that into a file, add a .css extension, then remove the Less.js script tag from the HTML pages and substitute the CSS file you just created.
Either way, use Less.js.
DeadBeef is actively developed and in a way that brings it closer and closer to Foobar2000.
(what it lacks in Foobar2000-features (numbers of addons) it compensates in being light and up-to-the-point - the most straightforward and non-bloated music player/handler I have seen until now in Ubuntu).
With File browser plugin:
With Infobar plugin:
to install it:
sudo add-apt-repository ppa:alex-p/deadbeef
sudo apt-get update
sudo apt-get install deadbeef
Or download as .deb and install (i686 or amd64)
To install plugins, wich are .so files
, they should be put into a certain folder.
~/.local/lib/deadbeef/
or: /usr/local/lib/deadbeef/
For the static portable version it is deadbeef-versionnumber/plugins
Considering problems of incompatibility and other issues in using the plugins, see this related answer
To convert audio files, see this question+answer.
Considering memory use, Deadbeef is much lighter than other players that might be considered foobar-like.
The latest versions (now 0.6.2) bring it even closer to foobar by the 'Designer mode' feature (similar to the layout editing mode in foobar) by which built-in or plugin features (file browser, infobar etc) are integrated to the interface:
File conversion is now very close to Foobar2000's - see the link above on conversion.
Already mentioned in answers, a great alternative is Clementine.
Best Answer
This question was originally another question, but it was edited or changed in at least 80% of the original question. However, this answer can yet be helpful for you.
You may wish to give a try to HardInfo or Phoronics which doesn't indeed do as many things as Sandra does, but it shouldn't as we are talking about Linux Systems.
Take a look at:
Hardinfo at http://hardinfo.berlios.de/HomePage
From the site: System Profiler and Benchmark HardInfo can gather information about your system's hardware and operating system, perform benchmarks, and generate printable reports either in HTML or in plain text formats.
I prefer to use Hardinfo, here is my screenshot of a benchmark in action in my system:
Phoronics at http://www.phoronix-test-suite.com/
From the site: The Phoronix Test Suite is the most comprehensive testing and benchmarking platform available that provides an extensible framework for which new tests can be easily added. The software is designed to effectively carry out both qualitative and quantitative benchmarks in a clean, reproducible, and easy-to-use manner.