Internet Explorer 0-day Javascript exploit

SANS InfoCon [1] has been raised to yellow today and for good reason; A  security researcher working for the UK company Computer Terrorism has published a 0-day remote code execution PoC [2] exploit.  This uses an older [3] vulnerability in Internet Explorer versions 5.5 and 6.0 thought to cause a DoS only.  More information is available in the FrSIRT advisory [3].  Currently the only available countermeasures that I am aware of are:

1. Disable all "active content" (i.e. Javascript and VBScript) in untrusted security zones
2. Use another web browser [4], at least for the time being (you might not want to switch back)
3. Detect or Block based on signature (there's a Bleeding-edge Snort [5] signature available here [6])

Be careful out there.