We believe that while toptable.com did contribute to a bulk of the increase in expenses, more particularly the indirect expenses, an important factor was a disproportionate increase in sales and marketing expenses.

FORBES: Some Reservations Over Cost Of OpenTable Growth

If he treats his avocation as a business and files a Schedule C, he can deduct all expenses, even indirect ones like going to guitar shows and buying tools and catalogs.

FORBES: Hobby Horse

Other consequences are the increased costs associated with prolonged illnesses, including expenses for additional tests, treatments and hospitalization, and indirect costs, such as lost income.

CNN: Antibiotics: Misuse puts you and others at risk