interesting question...

I think it would have to be one of these:

- Never catching a virus in a whole year without antivirus
- setting up xgl and watching my windows friends turn green
- 1 week of uptime (laptop, swsuspend)

Getting linux configured the way i like it.and starting x.

Hm...
I might just *have* to include some cool things about Linux itself, but I'll give it a try-
*Not having to worry about my computer restarting randomly because of Automatic Updates
*Having more than a 3 day uptime (I'm not really sure, but I restart my computer to switch OSes a lot, and I rarely have an uptime counter going)
*Converting two of my friends (I know for a fact that one of them has it installed and is usually in it) to using Linux
*Installing Linux more than 20 times successfully (four times of a physical disk, the rest in VMware (Player, Workststion, and Server)
*Learning some scripting
*Installing VLC and VMware (Player, Workststion, and Server)
*And lastly, not having to worry about some people from MS looking at my stuff (I don't have anything sensative, but I still like muy privacy)

Finding a distro (Ubuntu 6.06.1) that everything I use worked "out of the box".

Ability to play Unreal Tournament 2004 with maximum graphic settings and better sound quality than Windows.

Got a fully functional 160GB hard disk on a motherboard
that can only see 8.
Got 512MB of RAM on an Acer Travelmate 345T, when the
service manual (and a few dumb shop workers) says you
can only have 128 (this one maybe works with Win also...)

Coolest things? now let me see...
writing some cool shell scripts to automate certain redundant task
re-configuring and re-compiling my kernel
aliasing several commands with bash.bashrc
re-configure my bootloader
programming in python
getting my sound to work with SuSE 9.1
mastering the CLI and FTP
understanding the linux filesystem
Becoming all that i can be......

Seting up my company's first real server. Debian Sarge acting as a PDC (samba), DNS (bind9) and email (exim4 for SMTP) server when the old server was a W2KSrvr acting just as a simple file server. Little to no real authentication and no domain, just a workgroup. It's almost done and I'm just tickled about it. It does 10 times what the old server did, is capable of a thousand times more and I get to choose when to update, what updates to load and not have to worry about coming in in the morning to see the message "Windows was updated recently and required a restart..."

I guess the coolest thing I've done is using linux for editing photos professionally (most photographers say this can't be done, mac and windows are your only options!). HA! Got a rock solid install of Debian Etch running Photoshop 7.0 in WINE (no glitches BTW). I've completely dumped Windows and haven't looked back! SAY CHEESE!

Apart from setting up my current box as a router, there are only many small things I can think of right now. One of them occurred just yesterday:

I needed to print four 'presentation' sheets from a PDF document onto one page and didn't know how to quickly do this. First I tried to find some option for this in ghostview or xpdf, but had to resort to acroread (Acrobat) in the end. In Windows I would have had to do the following: press the 'print screen' button for every page and copy+paste+save each one in Paint. And then I still had the menus and scrollbars on every sheet (not good).

In Fluxbox, all you have to do is 'push' the menubars off the screen, open a small terminal and use import -window root -quality 90 newsheet.jpg

Edit: The page viewing needs to be set from 'Single page' to 'Continuous - Facing' first, of course. This option is in the lower right hand corner of acroread.

Created a self aware AI that now has control over the entire world with none of Asimov's laws to screw it up! The near future just arrived. mmmwaaahahahahah!!!

Coolest thing by far:
Dumping my windows partition and converting it to a linux partition.

O and playing Doom3 at higher res and more detail!

the coolest thing i have done??

convert my parents to linux. yep.. spyware and virus free for [edit]over[/edit] a year.

only had to make one (1) service call in a year (and that was a distro upgrage)

my father is 60, and has little to no computer experience.

yep.. i rock.

rm -rf /

true client/server network with nfs/samba/nis and 3 serial terminals in my own home, using a serial terminal with screen/vtclock/aumix/xcplay/naim/links to control the volume/playlist check the time, chat & browse the web from bed with the actual computer on the other side of the room, try doing that with windows