By John Zappe (was a newspaper reporter and editor until his geek gene lead him to launch his first website in 1994. Never a recruiter, he instead built online employment sites and sold advertising services to recruiters and employers.)

This year’s list of the Best Companies to Work For reads a lot like last year’s. The rankings have changed a bit; SAS, for instance, got unseated for the #1 spot by Google, but otherwise the list (click here for the list of all 100) shows that a great place to work tends to stay that way.

That’s because it’s no easy feat to win a spot in the top 100, whichFortune released today. Many companies compete — 1,000 typically start the process. They’re put through the wringer by The Great Place to Work Institute, which requires each to undertake employee and management surveys, examines employee engagement, and develops a Trust Index. The Index measures what the Institute believes are the cornerstones of a great place to work: Credibility, Respect, Fairness and Pride, and Camaraderie.

While economic and financial conditions influence the rankings, the Trust Index is the cornerstone of the ranking. Building a high Trust Index takes time and commitment from every part of the company, beginning with the CEO and C-suite. The culture that creates endures.

It doesn’t hurt, though, to offer great pay and great benefits. Fortune notes Google’s “free gourmet food, on-site laundry, dry-cleaning, and alterations, an outdoor sports complex, (and) the star-studded lineup of speakers.”

But even for perk-heavy Silicon Valley, three-time first-place winner Google offers an unrivaled assortment of benefits and perks, including custom workstations. Says Fortune, “One option that became increasingly popular last year was swapping out the standard sit-down desk for a standing desk. Googlers place an order with the company’s Ergolab, choose from a number of desk models, and have their desk measured to their height.”

Google isn’t alone in providing unusual perks. GoDaddy, #93 on the list, holds off-site activities that have included “whitewater rafting, gold panning, competitive cooking courses, and trapeze classes.” Zappos gives every employee$50 to award as a bonus to a co-worker. From those getting a bonus, the company picks a winner who gets a parade, special parking, a $150 gift card, and a cape.

For the complete list of this year’s best 100 companies and their 2011 rankings, click here.