I made the Big Switch from Windows to Linux at work several years ago, and never really looked back. For whatever reason, our version control system and builds are always about twice as fast on Linux compared to Windows. I'm also much more comfortable in a UNIX-y shell / scripting environment than I am in Windows Command Prompt, probably because of hours spent in various computer labs at university when I really should have been doing something more fun (like drinking beer).
As well as the raw productivity gain from the faster environment, I also customized my environment a great deal to minimize keypresses. For example, where most other people in my team might type something like this:
cd $ADE_VIEW_ROOT/jdevadf/modules/ide/src/oracle/ide
ade co -nc Ide.java MainWindow.java
cd `pwd`
emacs Ide.java MainWindow.java
cd $ADE_VIEW_ROOT/jdevadf
make release
I type:
m ide/src/oracle/ide
co Ide.java MainWindow.java
emacs Ide.java MainWindow.java
jdevadf
mrel
Doesn't seem like much, but over many many months and years of coding, all those extra keystrokes add up... Better still, I had some immensely powerful tools in my box that would invoke compound commands to provide interesting information.
So, if I wanted to quickly find a file in our source control system (an operation that can be sped up by grepping some version control metadata files, chopping the file up to make it readable), I'd type wi SomeFile.java (where is?). If I wanted to know which module (out of about 600 in our system) was responsible for delivering a jar file (again which involved a lot of grepping through multiple files and cleaning up the output), I could ask wm foo.java (which module?).
These utilities ran ridiculously quickly, because I figured out tricks that were somewhat specific to our system. For example, grepping the version control files to locate a file is way faster than using "find", since it's a grep on a single file instead of a directory tree traversal. Their real power was in compound commands. I could check out all files with the extension xml that contained the string "brian.duff" with a command like this:
wi '\.xml$' | xargs grep -l 'brian\.duff' | xargs co
This is all fine and great, but there's a huge downside. Every time I sat at someone else's terminal to help them with some problem and attempted to run some commands, I had to remember to type the longwinded versions of all these commands again. Like being thrown back into the dark ages. Worse than that, it actually slowed me down even compared to someone without the shortcuts, since my fingers would frequently forget and type my shortcuts instinctively even though my higher brain was fully aware that they wouldn't work. Finger memory is a strange thing.