Learn to say "no" diplomatically. The saying of "no" raises stock values.
Don't say it(at least not often), but be aware of the saying, "lack of planning on your part is not an emergency on mine."
Learn to set limits, but occasionally push them when necessary.
Don't leap on each question as a new challenge. Step back and think, "what else do I have going on now?" I know it's too too easy to do, but it's a quick way to become swamped.
Spread the wealth, learn to teach. These simple techniques that you elude to, take some promising initiate in your organization asside and make sure that they understand how they work. Go over the 'nuts and bolts'. Develop them into a resource onto which tasks can be offloaded. Invest a few hours of teaching today, to save a few days of work later.
Not a skill, but keep duplicate copies of Programming Perl and The Perl Cookbook on your desk. When someone comes around, "can you do X?", hand them a copy and say "X is in here, try this, and come back later and come back if you can't make it work." (make sure your name is on the side of the book)