Note: It turns out there is actually already a rather nice Microformats Cheat Sheet available (in PDF), by Brian Suda. That'll teach me to search for other cheat sheets before starting work on mine!
The Microformats cheat sheet is designed to be printed on an A4 sheet of paper and live by a designer or developer's desk, to make life a bit easier. A description of what is on the cheat sheet follows, or if you are impatient, you can go straight to the full size Microformats cheat sheet.
Further information on Microformats and their specifications can be found at microformats.org.
iCalendar and hCalendar
iCalendar is a common format for calendar documents on the web, and hCalendar is a microformat based upon the same standard. Essentially, it is a collection of attributes that allow you to identify events contained in an (X)HTML document. This section includes an example of an event in iCalendar and hCalendar formats.
hReview
hReview is a microformat that allows the marking up of reviews within (X)HTML documents. This section contains a sample review marked up with hReview.
vCard and hCard
vCard is a commonly used format for sharing contact details for people, and hCard is a microformat allowing you to mark up contact and personal information for people within web pages.
RelLicense and RelTag
RelLicense and RelTag allow you to add extra meaning to links within web documents, identifying links to licenses or that are used for tagging purposes.
XFN Format and Values
XFN is a microformat allowing you to identify relationships with people you link to within web documents, whether they are friends, family, co-workers or just people you once met. These sections show an example use of XFN, and a list of the valid values for XFN information.
Dates
Microformats use ISO 8601 format dates. This section details the specification, showing examples dates in their respective formats.
Download
So now that you know what it does, please feel free to print out the Microformats cheat sheet:
And finally, if you like the cheat sheets, and want to say thanks, please consider buying me something from my Amazon Wishlist. Thankyou very much to those who have already hunted it down and sent me something nice - I'm very grateful!
Please note: If you wish to link to the Microformats cheat sheet from elsewhere, please link to this page so others find the description, rather than linking directly to the sheet.

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But you really want Season 2 of Knight Rider?!
Oh Dave... you shouldn't want that, Dave.