PHILADELPHIA (TheStreet) -- Remember Scrooge McDuck -- the wealthy cartoon character who was always tight with a buck?

He embodies the spirit of the Bogleheads, devotees of John C. Bogle -- Vanguard founder, index-fund inventor and the father of investing on the cheap.

During a three-day annual get-together outside Philadelphia, many Bogleheads converged to discuss how to save and invest, to share tips, and to listen to Jack Bogle himself unleash his opinions on the market, politics and what investors should expect. 

The group coalesced in the late 1990s on Internet message boards, first at the Morningstar Web site, and then at a dedicated site, Bogleheads.org.

The 220-some registered conference attendees visited Vanguard headquarters and were greeted by Chief Investment Officer Tim Buckley, among other honchos. A spokesman for Vanguard described the Bogleheads as "our biggest fans and our harshest critics."

Bogleheads.org is the anti-Reddit: the site is known for its civility, where many posters use their real names, and the confessions of financial mistakes generally meet encouragement and disinterested advice. And there's one big topic: how to save and invest money.

The site's ethos is do-it-yourself. It's built around the little guy looking to save for the future and not get rooked in the process. The philosophy is simple: costs matter in investing, and with a plan to save and invest deliberately, the average person can retire comfortably. And those plans don't need to be complicated. Taylor Larimore, one of the founders of the Bogleheads group, often writes in praise of the "majesty of simplicity."

The forum has been hugely successful. As of September, Bogleheads.org received up to 4 million hits a day, with up to 70,000 unique visitors daily, according to Mel Lindauer, president of the nonprofit John C. Bogle Center for Financial Literacy, and also a frequent financial writer and prolific poster on the site. More than 2.5 million posts have been made since the site debuted in 2007.

Lindauer said the site's mission is wide-ranging: "to educate all American investors."

The site also features tools for new investors who are just getting started. The Bogleheads Wiki, an online encyclopedia, is maintained in part by a site moderator who prefers to use her online handle, LadyGeek. She explained why she volunteers on the site: "This stuff is complicated, and you're messing with your life savings.... This is my way of paying back." The Wiki explains the finer points of the site's mission: to give investing advice inspired by Jack Bogle.

So why base the site on Jack Bogle? And why embrace Vanguard, surely the only financial company with a passionate fan base?

Jack Bogle -- "Saint Jack" to his fans -- founded Vanguard in 1974 to be a company owned by its mutual fund shareholders. This true mutual structure means that profits are returned to the owners via lower and lower fees. (No other mutual fund company shares this structure, although a few compete with Vanguard on prices.)

Vanguard also pioneered the index fund. Instead of using a mutual fund manager to pick a subset of stocks in the hopes they'll appreciate, index funds instead buy every stock in their benchmark sector.

For example, its oldest index fund, the Vanguard 500 Index Fund(VFINX) - Get Report(VFIAX) - Get Report(VOO) - Get Report , buys stock in the 500 largest U.S. companies in proportion to their total market capitalization. (Its largest holding is Apple(AAPL) - Get Report , because it is the largest-cap company.) And the 500 Index's expense ratio is a measly 0.17% for its investor class, meaning that an investor with $10,000 in the fund would pay $17 a year to Vanguard in fees. Investors who invest more money or who use the ETF share class pay even less.

The Bogleheads' 14th meeting -- they've become annual affairs -- attracted a mixture of new faces and returning visitors. Tim Dempsey, along with Mel Lindauer and Jack Bogle himself, is the only attendee to participate in every one of those meetings. Dempsey described the annual meeting as "a trip to Mecca," where he could learn new things and get back in touch with Bogle's philosophy. He said he loves reconnecting with old friends and meeting new ones.

The audience is generally gray-haired and skews toward retirees -- a show of hands asking who is retired suggested that the number of retired attendees is near 50%, or maybe north of there. Many more are in what an attendee called "periretirement" -- the five years just before or just after retirement. Still there were attendees of every age from their 20s to their 90s. A discussion of Social Security strategies drew about 100 listeners.

Life seems good for many of these Bogleheads. Richard Zepnick, for example, rode his motorcycle on a road trip from Racine, Wisc., to Philadelphia for the conference, his second road trip this season. He rides a BMW -- fancy, but he got a good deal on it used, he said. Another attendee went on a 400-mile bicycle ride from Richmond, Va., to the conference. And another conference-goer said, "I'm a wear-a-Brooks-Brothers-shirt-till-it-wears-out and Dockers kind of guy." His wardrobe matched the description.

No expensive watches or expensive handbags were on view. And one presenter mentioned with pleasure that he used a 57-cent calculator from Wal-Mart (WMT) - Get Report -- then casually dropped that he used it in Hawaii.

With their modest cars and extensive discussion of coupons, the Bogleheads may not seem very glamorous. But they've figured out how to save, invest, retire and live large. They may seem cheap, but if you listen closely, you'll hear discussions of how it's annoying to polish chrome on a boat, or how shocking it is to discover how many Hawaiian shirts have piled up between their main house and the vacation house in Florida.

Life is good for these Bogleheads, even if every penny is a prisoner for them.