If you want to link any event or to do in your iCal calendar to a specific email in Mail (without using
MailTags), then here's how:
- Paste this text into Script Editor (or download the script) and save it to some directory (like your user's Library/Scripts folder, if you're using the script menu).
- Select the email you want to link, and run the script.
- After the beep, hit paste in the URL field of an event or To Do.
You can now open the linked email by clicking on the URL field in the inspector, and selecting Go to Location.