Imagine an online relational database management system that’s as easy to use, or even easier, than an online spreadsheet.

That’s the guiding idea behind Blist, a start-up that launched its online RDBMS with a Flash-based Web interface that’s designed to hide the fact you’re actually working with one of the most complex software applications.

Blist was unveiled Jan. 28 at Network World’s DEMO 08, a showcase for new technology products and companies. (A video of Blist’s presentation is available on Demo.com).The company is betting that lots of folks, from small business owners tracking sales, to fantasy football players and recipe hoarders, are ready, willing and able to give up using Microsoft Excel for data management and turn to database technology delivered as an online service.

Blist uses the established open source PostgreSQL database engine for numbers and similar data that are the traditional domain for a RDBMS, coupled with a highly scalable distributed file system for documents and other stuff that won’t “fit” into the RDBMS. The Blist database stores a bunch of metadata about these external files so they can be found and manipulated quickly.

The company is developing a data management architecture similar to what Google has developed to drive its search engine: thousands of computers that will be able to break down a problem or query into pieces, process the pieces in parallel blazingly fast, and then pull all the pieces back together and present the results.

Blist founder Kevin Merritt is a software engineer who spent six years as CIO for brokerage house Smith Barney. He also is founder and former CTO of MessageRite, an online e-mail archiving service that Microsoft acquired in 2005. He spent a year MessageRite and started Blist early in 2007.

Most people who aren’t database administrators use a spreadsheet such as Excel with its rows and columns to organize data, Merritt says. “It starts out OK but then it runs into problems, for example, when you need to store multiple values per row.”

For example, in tracking job applicants’ qualifications, this means having a value called “education” for a candidate’s college degree, but wanting additional details nested within, such as the school graduated from, year of graduation and so on. “We make it easy to do that,” Merritt says.