If you have obtained your own health insurance policy and are paying for your own or your family's health insurance, then you may be able to take a deduction for self-employed health insurance on the front of the Form 1040, Line 29. Basically this is a deduction of the full cost of your health insurance premiums. You cannot take this deduction for any month that you were eligible to be covered by an employers' health insurance plan, either your own, or that of your wife or children.
An important consideration for 2010 tax returns only is that this self-employed health insurance deduction will also be used as a deduction in calculating your self-employement tax (Schedule SE). If you forgot this deduction on your 2010 return, you should review it and consider filing an amended return (Form 1040X)
Watch to see if this special deduction from Schedule SE gets renewed for 2011 or future returns, but as of May 2011 it has not been renewed and is considered a 2010 deduction only.
IRS Publication 502 has more detail on this.