Now that Barry Bonds has joined Willie Mays in the four-member 600 homer club, expect the heat to turn up even more on Bonds memoribilia. (Al Behrman/AP)

The milestone has vaulted Bonds back to the forefront of the public eye and minds of collectors. And the latter love a good bandwagon when they see one. Bonds' record-setting 73rd home run baseball was expected to fetch more than $1 million at auction this offseason, but a dispute over the rightful ownership of the ball between Giants' fans Alex Popov and Patrick Hayashi has that ball tied up in court. A San Francisco trial over the fate of that baseball is set to start on Oct. 9.

BONDS HITS 600TH HOME RUN   With his solo homer in the sixth inning Friday against the Pirates' Kip Wells, Barry Bonds became the fourth man in history to hit 600 home runs. Bonds joins Babe Ruth, Willie Mays and Hank Aaron. more> • Career stats: Aaron | Ruth | Mays | Bonds Bonds' 600th: 56K | 300K   Photos Radio calls: English | Espanol Postgame: Press conference Photo Galleries: Aaron | Ruth | Mays | Bonds Wallpaper: 800x600 | 1024x768 Bonds Shop: Buy Barry Bonds gear >       Complete coverage at Mt. Crushmore >

"There have only been three 600 home run balls hit and none of them have ever hit the open market, so this will be very interesting," said Michael Barnes of Barnes Sports Group, who has brokered the sale of many home run baseballs, including Mark McGwire's 70th home run ball from 1998 that sold for $3.05 million to Todd McFarlane. "I would have to say that this ball could be worth $250,000 to $500,000 because there's never been one before. Even his bat from that home run could command up to $100,000 or more. But the more interesting aspect is where it will land since we've seen what can happen in San Francisco."

Legal wrangling may still have "Bonds' 73rd" in limbo, but collectors had plenty of other items to choose from last winter after the slugger's record-breaking 2001 season. His 70th home run baseball sold in April during a MastroNet auction for $60,375. Eighteen other Bonds items sold well, with an autographed bat used to hit home run No. 68 in 2001 selling for $32,766, while the jersey he wore the night he hit his 547th home run sold for $25,558. Even several home run baseballs that were hit into McCovey Cove last year and retrieved by fans sold for between $2,990 and $4,817. A complete run of unused tickets from 2001 Bonds home run games sold for $8,210.

And while there's obviously plenty of value for the 600th home run ball today, industry experts emphasize that the real value lies ahead, especially if Bonds continues to forge closer to Aaron's MLB record of 755 career homers.

"I think the real key with Bonds is what he does over the next two years," said Brian Marren, VP of acquisitions for MastroNet.com. "If he gets near 700, interest in all of his stuff is really going to increase. That's more of a benchmark than 600, although 600 is obviously a great, great accomplishment. If he has two more years of 50 or more, his name becomes even more prominent and draws even greater demand. Then everything from him reaches a new plateau."

Bonds' accomplishments over the last two seasons have vaulted him into a higher echelon among collectors. His 1986 Donruss ($30), Fleer ($30) and Topps ($15) rookie cards have all doubled in value since the start of the 2001 season and many of his high-grade cards are selling for high prices. A pair of 1987 Fleer PSA 10 rookie cards sold for $580 and $560 recently, solid prices indeed.

Bonds' autograph remains a desired one, with an autographed baseball priced at $125 and an autographed bat priced at $500. Bonds rarely signs at card shows, but he did make his eighth show appearance since 1988 in December at a special tribute to him in Atlantic City. Bonds became the newest member of the 500 Home Run Club last year and he wanted to give those collectors a chance to get their 500 Home Run Club items signed by him. The price was $225 for a signed baseball, $325 for a signed bat and $625 for a signed 500 HR Club jersey or bat. Bonds will also have an announcement soon on a special autographed bat deal commemorating his 600th home run that will sell shortly after he reaches that milestone with prices set at more than $1,000 per bat.

For those who have just a little less money to spend on their hero, Bonds bobbleheads have been popping up as fast as homers have left ballparks. Bonds has 13 different bobbleheads -- 10 that have been produced this year -- ranging from $20 to $60 apiece.

It's all part of the collectibles life of being a famous slugger, one who just joined the Elite Three on the Mount Rushmore of home run giants.

Greg Ambrosius is an associate editor of Sports Collectors Digest, the sports collectibles industry's premiere weekly publication. Contact Greg at scd@Krause.com.