MINNEAPOLIS - When Caribou Coffee went public last year, sharp-eyed investors noticed some unusual promises in its prospectus. Caribou, the nation's second-largest coffeehouse chain, said it would never sell pork or porn. It wouldn't charge or receive interest, either.

By following financial rules that are part of the Islamic code called Shariah, Caribou is among a small but growing list of Western businesses looking to make themselves as attractive as possible to Muslim investors. Some, like Caribou, are motivated by principle, while others see Muslim investors as an attractive new source of money.

Middle Eastern investors flush with oil profits are looking for new places to invest, and American Muslims are looking to invest in a way that doesn't conflict with their faith.

"There's a bunch of Islamic investors who are prohibited from a lot of regular investments, so a lot of money is sitting in cash not earning anything at all," said Khalid Howladar, a vice president for Middle Eastern and Islamic Structured Finance with Moody's Investors Service in London.

Companies and governments who need to raise money are saying, "'There's a bunch of people out there with money they can't spend — how about I create something for them?'" he added.

Dow Jones has created an Islamic investing index. A Texas company issued almost $166 million in Shariah-compliant bonds to finance natural gas operations in the Gulf of Mexico. And the German state of Saxony-Anhalt issued a floating-rate 100-million euro note — managed by Citigroup — that followed Shariah rules.

Assets invested at two Shariah-compliant funds run by Saturna Capital in Bellingham, Wash. have swelled nearly 10-fold, since 2002 from $34 million in 2002 to $331 million now — though that's still tiny by mutual fund standards. The funds invest only in companies that are Shariah-compliant...