Harness Server Controls
When you write a Server Control and write it well, it pays off immensely. Today, I needed to rework our Custom Defaults screen (a screen that allows each user to define defaults for our quoting screens to use each time they write a new quote). All of the fields on the Custom Defaults screen exist in the quote (duh, why would we provide something that didn't? 
).
Since everything in the quote is a server control, it was just drag and drop the controls onto the Custom Default page and it would act 100% like it does in the quote. 
It could not have gone any faster, I probably only spent close to 5 minutes setting up the design and flow and 30 minutes getting the code behind functionality to work.
Thus, harness the power of Server Controls as they can be reused across numerous applications with little trouble and little programming.