Ask HN: Whats the coolest software you've ever seen or used?

Definitely MS Excel.

Proof: The enormous number of variations that people are using it except from its original usecase of a calculating spreadsheet

Harry's Lap Timer[1]. It's amazing what this program can do, exploiting nearly 100% of the iPhone hardware. I remember that the battery wasn't even charging while I was racing. It was connected to the USB car docker, but it was steady at 75%.

[1] http://www.gps-laptimer.de

FoxBase +/Mac 2.x - it was one of the dBase 3+ clones, this one was geared directly on the Mac.

It got way more right than just the databse, well integrated quickdraw libraries and could do graphic forms and such and given the way it was designed you could graphically generate full printed pages as well, and get help using the output from the form builder to help you work out the code. Very fast, easy to program.

I think it all was all about 800K app, compiled from C.

Even the developers got turned on to the superior Mac version (I have promotional material from the time somewhere talking about how everyone at fox was getting Mac religion. You can get an idea from this article - http://www.foxprohistory.org/interview_fox_to_mac.htm )

That changed once Microsoft took Fox software over, started standardizing the FoxPro Line to windows standards (foxels... shudder)

Amiga - Deluxe Paint 2 was incredible when I first saw it, especially the concept of working with HAM although it wasn't so practical to use those images. DP3 was an awesome intro to animation also. Photon paint was pretty cool too, although I seem to remember waiting a long time for effects to render.

google earth. Around 2005 or 2006 when i saw it for the first time i was blown away.

The symbolic calculus capabilities of Maple still blow my mind.

SketchUp

You can sit down and do 3d without knowing anything about the program. Things like Maya, Blender or 3ds Max require training to achieve almost anything.

Fireworks

I can only wonder how amazing it could be if it was split out from Macromedia before it was bought by Adobe.

IntelliJ Idea

Type hints were amazing. For the first time I felt like having actual conversation with the computer about what I want to achieve. Too bad it didn't progress at all since then.

I always had high respect for google maps.

The original Elite on the BBC Micro. Coded in assembly by 2 people as a summer project. Used procedural generation to create a universe of thousands of star systems, all fitting into 32kb of memory. It's just incredible what they achieved.

Houdini from SideEffects.

Saw it used in school in 1997. Left a job because they wouldn't get a license of it for me in 2007 (after stringing me along for a year). Have been happily using it at work since at different studios around the world.

Besides from Excel and Maps which have been mentioned: Facebook because of how it used javascript. Most message boards at the time had page reloads/redirects/wait screens after posting.

Leo (http://leoeditor.com) pretty much blew my mind when I figured it out. Changed the way I see data.

(Full disclosure, I contribute to Leo now.)

I'm constantly amazed by minecraft. Its a world within itself.

The original Civilization game, pretty much blew my mind.

Google Maps still impresses me in the ability to go look at almost anywhere in the world. Likewise for Wikipedia if that counts as software.

Sketchup is definitely cool. The most user-friendly (professional capable) software I know.

Autocad is also great. An emacs for CAD.

Resolve (a Boole and Babbage product), on MVS mainframes. Incredibly powerful for its time.

probably ophtcrack or Kali Linux distro, always amazed when I see nice looking front end software designed to exploit known vulnerabilities.