There are a number of steps you might take by year-end to cut your 2011 tax bill, such as deferring income, accelerating deductions and capital gains planning.
If you are planning on selling an investment this year on which you have a gain, it may be best to wait until the following tax year to defer payment of the taxes for another year (subject to estimated tax requirements).
If you are expecting a bonus at year-end, you may be able to defer receipt of these funds until January. This allows you to defer tax payments (other than the portion normally withheld) until the following year. However, keep in mind that you usually defer taxes on a bonus that is contractually due in 2011.
If your company grants stock options, it may be wise to wait until next year to exercise the option or sell stock acquired by exercise of an option. Exercise of the option is often but not always a taxable event; sale of the stock is almost always a taxable event.