Okay, so there are some people that prefer using UNIX (That's Mac OS X, GNU/Linux, the BSDs, etc) to Microsoft Windows. In that case, you need to use a program called Wine to play. If you like using the command line interface, like I do, here's a guide to getting Ace of Spades to work, and play well:
(In these instructions, I am using ## in place of the version number. Remember to change this. Tab completes in most shells, but make sure you're in the same working directory of the installer if you don't want to type the full path out.)

chmod 755 aos*install.msi && wine start aos##install.msi
This makes the installer executable, and starts it.

nano ~/.wine/drive_c/Ace\ of\ Spades/config.ini
This is for changing your name. Nano is recommended for beginners, but any plaintext editor works.

echo "wine ~/.wine/drive_c/Ace\ of\ Spades/client.exe -$1" > aos && chmod 755 aos
This makes a small script you can use to start playing from the command line.

echo "wine ~/.wine/drive_c/Ace\ of\ Spades/server.exe" > aoserv && chmod 755 aoserv
...Alternatively, you can also have one that starts a server. I'd use this in GNU Screen.

sudo cp aos /usr/games
Now let's add this to our path. If this folder isn't in your path, see what is by typing "echo $PATH". You'll probably need privileges to copy the script there.

aos aos://16777343
When you want to play, just type aos and paste the server URL. This example would connect you to a server on your rig (localhost).

I hope this helps! Feel free to copy, modify, or distribute; it's public domain.

"Bob''

Very nice guide, A+

I'll try it with Ubuntu.

All this coming from a guy that only types in caps ingame and tells people to suck his dick after he kills them.

Are you two different people at the same time?

Nice guide, though.

So I tried. I entered all these things and don't work at all. Used this http://aceofspadeswiki.com/index.php?title=Linux and doesn't work.

Now it shows "Error: Visit ace-spades.com to join games or try a different server" and than Wine Windows style error and debugger in console.

Zaqq, can you play by running the command "~/.wine/drive_c/Ace\ of\ Spades/client.exe -aos://blahblahblah" ? I tried this on Slackware Linux as well as Gentoo Linux. I'm just assuming that it would work with Macs (if that's your OS) because BASH is BASH.

Ubuntu. Yes! It works! But no sound (maybe my mistake) and cursor is over the crosshair (I'll fix this, I think).

No thank you, we don't want Mac users here.

I keep getting an error saying please go to ace-spades.com to join a server. And is there an easier way than going rightclick>view source etc. ?

You're probably starting client.exe without any parameters. You need to start it this way:
wine client.exe -aos://16777343

Of course you change aos://16777343 to any server you want to connect to.

You should consider using a server browser to make the whole process easier.

Oh, that's right. When it echos, it ignores the $1 .

So, instead of:

echo "wine ~/.wine/drive_c/Ace\ of\ Spades/client.exe -$1" > aos && chmod 755 aos

do this!

echo "wine ~/.wine/drive_c/Ace\ of\ Spades/client.exe -\$1" > aos && chmod 755 aos

My stupidity explains why people were having problems connecting.

Pssst... BSD doesn't have any flavour of Wine on it. It has native support for Linux software but it's obviously imperfect. So I wouldn't just tell BSD users to go compile Wine for their systems just like that. I'm not an expert on this, I use openSUSE but there, just a tip mate. :3

Bob: Did nothing.

Szuwar: I got an error saying that client.exe doesn't exist

Bob, do i have to download Wine? Where can i get it? None of these instructions ask for Wine or the aos52install.msi.

I thought that it was implied.

http://www.google.com/search?q=wine

After a bit of jiggling, it works, but without sound. Anyone else encounter this?

@GeneralJoe

Go into your wine config, then the audio tab and set the hardware acceleration to "Emulation". Sound should be working perfectly afterwards.