If you're running the latest version of Parallels Desktop (and you should. The latest version as of this writing is version 3.0) then it makes this task quite easy once you can wrap your brain around how Windows stores data and organizes your [virtual] disk.

I have been learning how to create mind maps with Mindjet Manager Pro, a Windows-only application, and have using it within Windows XP on my own version of Parallels. Like you, I'm co-developing a mindmap with someone else and frequently need to email my modifications to him.

What I do, however, is open up a message to him in my email program (I use Microsoft Entourage rather than Apple Mail, but the process is basically the same) and choose "Add Attachment". Then here's what I see:

Notice the set of drives and devices on the top left? The one we want is conveniently labeled [C] WinXP. Click on that and now we're looking at the top level "C:" drive from the Windows world of Parallels:

[Important note: you can only see this device when Parallels is actually running. If you pause it the device vanishes from your Mac desktop]

Microsoft Windows has a baffling top-level file organization. Unlike Macs where your files are all in the logically named "Users" area, or Unix and Linux where it'd be in "/home", on a Windows system you'll want to open up "Documents and Settings", which shows the home directory of each configured user on the Windows XP system:

Now you'll need to know which user you selected when you logged in to your Windows XP system to do the work. I violated Windows safety rule #1 and used "Administrator" when I was working on my mindmap, so that's what I'll want to choose. Really, it'd be far better if I used a named, non-administrative account, but, well, que sera, sera. :-)

Now you can see the "Desktop" folder: if you're dropping your work files on your Desktop, that's easy to open and access. If you're using the more standard Windows "My Documents" area, you can also see that's an option here too: click on "My Documents" and you'll be able to find your file.

Either way, once you have found and highlighted the desired file, simply click "Choose" and you'll have attached it to your outbound message:

That's all there is to it. Easy!

And a helpful tip: when you get a revised version of the file from your colleague, you can also save it to the [C] WinXP drive and have it show up directly within your Windows environment with no fuss and no intermediate file copying required.