AIM® Triton
Version: 2.2.71.1  25 May 06
Demo http://www.aim.com/triton/demo.html
Installer method....
Download:  http://www.aim.com/get_aim/win/latest_win.adp
File Name: AOLDNLD.exe 396kb then aolsetup.exe 974kb then the remaining is done via installer...
Download Size: 14.2 MB
System Requirments:
AIM Screen Name https://my.screenname.aol.com/
Windows XP, Windows 2K, XP 64 Bit
Microsoft Internet Explorer 6.0
128MB RAM
Macromedia Flash
Microphone/Speaker or Headset for Talk functionality
previous: 
1.04.1 29 March 06
1.04 26 January 06  

AIM® for Windows
Version: 5.9.3861 10 August 05
Download: http://www.aim.com/get_aim/win/other_win.adp
File Name: Install_AIM.exe
Download Size: 8.31mb
via ftp....
Download: ftp://ftp.newaol.com/aim/win95/Install_AIM.exe
File Name: Install_AIM.exe
Download Size: 8.31mb
System Requirments:
AIM Screen Name https://my.screenname.aol.com/
Windows 98/ME/2000/XP
IE 5.5 or higher
128MB RAM
20MB of free hard drive space (40MB of temporary space for the installation)
56.6 modem
Internet connection that allows full Internet usage (not just a free email service)
800x600 resolution, 256 colors or more
Full duplex sound card
Video IM requires Window XP
NOTE: Windows 95 users need to use version AIM_4.8.2790 (2.72mb) from http://ftp.newaol.com/aimgen/380465/Install_AIM_4.8.2790.exe

AIM® Version Links:
Using AIM on Windows ~ http://www.aim.com/help_faq/using/win/aimandother.adp
Windows Error Messages ~ http://www.aim.com/help_faq/error_mess/winerrors_buddylist.adp

AIM® for Mac
Version: 4.7 18 February 04
Download: http://www.aim.com/get_aim/mac/latest_macosx.adp
File Name: aim.bin
Download Size: 3.40mb
via ftp....
Download: ftp://ftp.newaol.com/aimgen/73010/InstallAIM4.7.bin
File Name: InstallAIM4.7.bin
Download Size: 3.40mb
System Requirments:
AIM Screen Name https://my.screenname.aol.com/
PPC running OS X.1 (or later) -OR- OS 9 with CarbonLib 1.3.1 (or later)
128MB RAM
20MB of free hard drive space (40MB of temporary space for the installation)
56.6 modem
Internet connection that allows full Internet usage (not just a free email service)
800x600 resolution, 256 colors or more
Full duplex sound card
NOTE: Mac OS 8.6 users need to use version 4.3 (3.49mb) from http://ftp.newaol.com/aim/mac/InstallAim_4_3.hqx

AIM® Version Links:
Using AIM on Macintosh ~ http://www.aim.com/help_faq/using/mac/aimtalk.adp
Macintosh Error Messages ~ http://www.aim.com/help_faq/error_mess/macerrors_applicationlaunch.adp

AIM® for Linux
Version: 1.5.286
Download: http://www.aim.com/get_aim/linux/latest_linux.adp
Red Hat 6.0, SuSE 6.4, Mandrake 7.0~
File Name: aim-1.5.286-1.i386.rpm (1.07mb)
Download: http://ftp.newaol.com/aimgen/380469/aim-1.5.286-1.i386.rpm
Debian 2.1 ~
File Name: aim_1.5.286-1_i386.deb (1.07mb)
Download: http://ftp.newaol.com/aimgen/380469/aim_1.5.286-1_i386.deb
Debian 3+ ~
File Name: aim_1.5.286-2_i386.deb (1.07mb)
Download: http://ftp.newaol.com/aimgen/380469/aim_1.5.286-2_i386.deb
All other OS ~
File Name: aim-1.5.286.tgz (1.06mb)
Download: http://ftp.newaol.com/aimgen/380469/aim-1.5.286.tgz

AIM® Version Links:
Using AIM on Linux ~ http://www.aim.com/help_faq/using/linux.adp
Linux Error Messages ~ http://www.aim.com/help_faq/error_mess/linuxfaq.adp

AIM Express®
http://www.aim.com/get_aim/express/aim_expr.adp
You need to have an AIM Screen Name https://my.screenname.aol.com/
Features:
Send instant messages
• See who's online in your buddy list window
• Start or join buddy chats
• Block members who misbehave
System Requirements:
Windows 98/SE/MP/2000/XP
• Internet Explorer 5.5 or later or Netscape 7.1 or Mozilla 1.4+ or Firefox
• Popups enabled
Mac OS X
• Netscape 7.1 or Mozilla 1.4+ or Firefox
• Popups enabled
If you don't meet the minimum system requirements for the lastest AIM Express, you can try AIM Quick Buddy http://www.aim.com/other/quick_buddy.adp