A more level playing field: Some major online retailers have started voluntarily collecting sales tax on all Internet sales (and not just those within their own state), as part of a deal with 38 states that are looking to collect sales tax from web-based merchants. The deal would essentially give the dot-com retailers amnesty from any effort to pay back taxes. The Washington Post reports:

Under current federal law, Internet merchants must charge applicable sales taxes if the buyer is located in the same state as the company. But the new deal effectively applies the same sales tax laws to retailers' online and bricks-and-mortar operations. Online units are often chartered as separate entities and maintain physical locations in only a handful of places, thus exempting customers from most states from paying sales taxes.

For example, Wal-Mart has 1,500 stores scattered across all 50 states, but WalMart.com, a separate subsidiary, has a physical presence in only nine states.

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Yet another sign the dot-com bonanza is over and online retailers will have to make money the old-fashion way.