What!?!? Blasphemy you say? Yes, here's how to run Internet Explorer 5.0, 5.5, and 6.0 on Linux.
Installation instructions for Ubuntu:
1) Open a terminal
2) Open /etc/apt/sources.list
sudo gedit /etc/apt/sources.list
3) Uncomment (or add) following lines:
deb http://us.archive.ubuntu.com/ubuntu gutsy universe
4) Add this line:
deb http://wine.budgetdedicated.com/apt gutsy main
5) Close gedit. Update and install wine and cabextract:
wget -q http://wine.budgetdedicated.com/apt/387EE263.gpg -O- | sudo apt-key add -
sudo aptitude update
sudo aptitude install wine cabextract
6) Download IEs 4 Linux and install
wget http://www.tatanka.com.br/ies4linux/downloads/ies4linux-latest.tar.gz
tar zxvf ies4linux-latest.tar.gz
cd ies4linux-*
./ies4linux
If you need instructions for your specific Linux distribution, check the ies4linux installation page.