A caution of advise is that it is always prudent and safe nowadays to claim only legitamate expenses when filing your personal tax return. With the current IRS audit environment, an audit adjustment can be potentially very expensive.
However, that should not deter you from claiming your allowable business expenses. An Office at Home usually results in additional IRS scrutiny, so please follow the rules regarding claiming an Office at Home.
Now, for additional ideas and suggestions please refer to this link that provides some of the typical expenses that a consultant may be able to claim. Tax savings strategy for self-employed IT consultant