Improving Access to Mainstream Financial Institutions Act of 2008 - Authorizes the Secretary of the Treasury to award grants, including multi-year grants, to specified eligible entities to establish an account in a federally insured depository institution for low- and moderate-income individuals who currently do not have such an account. Includes among such eligible entities: (1) Alaska Native Corporations; (2) Native Hawaiian organizations; and (3) labor organizations.
Authorizes the Secretary to award demonstration project grants to eligible entities to provide low-cost, small loans to consumers that will provide alternatives to more costly, predatory payday loans. Requires such entities to be: (1) tax-exempt charitable organizations; (2) federally insured depository institutions; (3) community development financial institutions; or (4) partnerships comprised of one or more of such entities. Requires grant recipients to offer financial literacy and education opportunities to each consumer provided with a loan pursuant to this Act.