Marketers love widgets and their ability to spread across the web and various social networks. But with developers asking for more compensation, far-reaching widget campaigns can carry a hefty price tag.

According to a BrandWeek story, marketers are beginning to have qualms about large widget campaigns because the fees they must pay developers have the potential to put serious dents in their budgets. Marketers often pay a developer to create a widget and are billed for serving the application onto a portal, like MySpace, Facebook or Yahoo. Developers then bill the marketer every time a widget is installed on a user's profile, sometimes to the tune of $1 to $5 per install.

Marketers contend that if a widget turns into a viral hit with millions of installs, it could lead to a quickly vanishing budget.

"The client or ad agency will have difficulty figuring a budget for that widget because they can blow through that in a short period of time or if the widget doesn't succeed, they could be left with unused money at the end of the campaign that they could have spent simultaneously on other media," said Peter Kim, CEO of Interpolls, a widget maker that only charges clients for a CPM.

Marketers spent $15 million developing and disseminating widgets in 2007, and that figure is expected to rise to $40 million this year, according eMarketer. That represents 2.5 percent of the $1.6 billion marketers will spend on social networks this year.

The battle for developers to make money off of their widgets is nothing new. Earlier this year, MySpace began charging developers to have applications featured on the widget hub page, leading to fears that smaller developers would be pushed aside. This week, AOL unveiled a plan that will pay developers a flat rate for using Platform-A technology in their apps.