Whew! I just crossed off two items on my Things to Do by the End of the Year push. Your list might include “sell stock to offset capital gains.” My big one was “buy windows to take advantage of the tax credit.” Now I won’t, and I can tell you not to rush.

Unless you manage to order and install those windows by December 31st, you can’t claim them on your 2009 tax return, so why rush?

I asked Gregg Semanick, the friendly IRS PR guy, about that. “Taxpayers must claim the credit on the tax return for the year that the improvements are made,” say the rules.

The 30 percent tax credit is worth looking at though, for certain income ranges. See Form 5695, Residential Energy Credits if you are interested for this year or next.

Maybe you can cogitate on some other kind of energy improvement to install by December 31.

Better idea: put that money in a Salvation Army kettle. My fellow Methodists and I have been ringing the bell at Palmer Square, at the Princeton Public Library, and in front of the church at Nassau & Vandeventer. Look for the kettle — and have a blessed holiday.