Pub 544, Chapter 4, Page 37, Center Column:
http://www.irs.gov/pub/irs-pdf/p544.pdf "Treatment of Capital Losses
If your capital losses are more than your capital gains, you can deduct the difference as a capital loss deduction even if you do not have ordinary income to offset it. The yearly limit on the amount of the capital loss you can deduct is $3,000 ($1,500 if you are married and file a separate return)."
