Guy Kawasaki 
, former Apple Fellow, Forbes.com columnist and venture capitalist, passed the time flying from Denver to San Francisco by knocking out twelve tips that will make you a better emailer.
The usual suspects, which it never hurts to read again, are there—sensible subject lines, plain text, short (ideal=5 sentences), avoid attachments—but there are two tips on the evils of FUQing (”Fabricating Unanswerable Questions”) that will make my emails better.
[...] Thanks to Tim Gaden’s great Hawk Wings website — which even though is all about Apple Mail tips, is good to read to pick up things like this — I have discovered Guy Kawasaki’s tips on better e-mailing. [...]