Amir Johnson: The last high school player to be drafted in the NBA, the 23-year-old Johson recorded career highs in points (6.2) and rebounds (4.8) in just 17.7 minutes per game in 2009-10. Like many of the bigmen on this list, he has a limited offensive skill-set, but has shown flashes of putting it all together. In five starts last season, Johnson averaged 17.8 points (70% FG, 86% FT), 6.0 rebounds, 1.0 blocks per game, including back-to-back contests with over 20 points to end the year.
While he's not particularly strong (and I'm being kind here) at 6 '11" and 210 pounds, Johnson makes up for his lack of size with energy and hustle. The versatile forward-center has the makings of a poor-man's Marcus Camby, and with more consistent playing time in Sacramento, could develop into a terrific complimentary post player in due time.
Shaquille O'Neal: Although O'Neal is clearly past his prime and has missed an average of 20 games per season over the last 15 (!) years of his career, he's only a year removed from an All-Star campaign with the Phoenix Suns. He put up career lows across the board last year, though his per-36-minute averages (18.5 points, 10.3 rebounds, 1.8 blocks) indicate that he still has something left in his tank.
Would the 38-year-old Shaq go from vying to "Get the King a Ring" in Cleveland to trying to get the Kings — the team he, infamously referred to as, "The Queens" — to win 35 games? Shaq is far more likely to continue his tour around the league with a another championship contender, and even if he is willing to go to Sacramento, he brings little upside and far too much baggage.
Joel Przybilla (ETO): Przybilla has found his niche as a defensive-minded backup center and spot-starter who provides rebounding and blocked shots. While his 2009-10 campaign was cut short due to a knee injury, he led the league in both defensive (33.1) and total rebounding rate (22.8) the previous year, and has averaged 1.6 blocks per game during his career.
The man affectionately known as "The Vanilla Gorilla" doesn't contribute much on offense — as in, the fewest points per game (4.2) of any starting center this side of Jason Collins — but moves well without the ball and has the size you can't teach (7' 1", 255 pounds). He'd make a safe, though obviously not an overly exciting stop-gap for the Kings if he opts out of the final year of his contract ($7.4 million).
Zydrunas Ilgauskas: Big Z split time at center with Shaq last season, and likewise had the worst statistical season of his career. While his defense and rebounding (9.3 per 36 minutes) remain sound, Ilgauskas, much like Hawes prefers to spot up for mid-range jumpshots at the expense of playing in the post. While he's shot 48% from the field over the course of his career, the 34-year-old converted an alarming 36% of his attempts away from the rim last year. No thanks.