You (and anyone reading this great list of recommendations) should try cmder. It's a customized build of ConEmu with lots of goodies thrown in.

http://bliker.github.io/cmder/

Can confirm, cmder is great, it makes console use on Windows bearable.

I have moved away from windows and miss Fiddler the most. It's ability to record, filter, edit and replay requests made debugging a breeze.

I like Mitmproxy. http://mitmproxy.org

Charles Web Proxy? Not free, but I've been using it very reliably on all platforms for at least 3 years now. :) A nicely polished bit of software. Free 30 min "trial mode" and no-cost upgrades, if it helps. Otherwise I've also used mitmproxy, or for some things, the Net panel of Chrome Dev Tools.

They seem to have Fiddler for Mac and Linux now (alpha version) http://fiddler.wikidot.com/mono

Try the proxy in Burp Suite. The free edition lets you do most of what you can do in Fiddler. More powerful in some ways, rougher around the edges in other ways.

WinMerge is not that good. BeyondCompare is in a league of it's own when it comes with diff apps (it's commercial though).

I can vouch for the rest too....ConEmu especially is very very nice.

I've had it installed on a bunch of corporate boxes and never used it and I'm not sure if anyone used it.

Even though it's a bit crash happy on windows and the gtk file picker sucks on windows for my uses meld was the most useful(at least now they have a packaged version for windows - http://sourceforge.net/projects/meld-installer/ - so you don't have to package it yourself). It's simple, good looking, highlights the difference between 2 slightly modified lines, has support for comparing directories, and allows in-place editing.

I prefer Meld on Linux and yes on the odd day, Windows.

I've got a couple other utils I'd add to a list like this:

- kitty (ssh client, fork of putty) - visualwget (wget gui) - dsynchronize (dir sync)

When I'm on Windows I use Cygwin ssh but for those who are more Windows aware, BitVise Tunnelier.

Another great SSH client is SmarTTY.

I came across this last week, a colleague wanted to open up an X window on his Fedora VM, shown in his windows box. SmarTTY just worked ootb, it was pretty amazing!

I'm partial to PuTTYTray.

Another one - crossplatform http interception proxy like Fiddler - called mitmproxy. It has a great feature - it can transparently handle https traffic.

I've been looking forward to having WinMerge on Linux for so long. I haven't found a good alternative on Linux which can do quick side-by-side comparison just by pasting from clipboard.

If you're on vim side - vimdiff does comparison just right. Though one'd need to tweak it to support comparing stuff from clipboard.

I'd add VirtuaWin for virtual desktops

and of course Emacs for Windows

You don't need gow if you are using msysgit right?

8) FileSearchEX for searching through source code files

Git Extensions for git are very nice too