NEW YORK (CNN/Money) - The stock market looks set to chalk up respectable, but not mind-blowing gains for 2004.

Investors in index funds should be satisfied, but maybe just a little bit envious of investors in these 10 companies, which range from high-profile techs (wish you had a bite of that Apple?) to insurers and steelmakers.

Following are the S&P 500 stocks with the biggest year-to-date gains as of Monday.

Apple: 200.3 percent -- Why have shares of Apple nearly tripled this year? One word: iPod. Sales of Apple's popular digital music player surged in 2004, helping Apple to blow away analysts' earnings estimates for the past three quarters. It looks like Apple is no longer just a company for faithful Mac users.

Autodesk: 214.3 percent -- There's been no slump for this maker of animation and image rendering software. Thanks to a booming construction market, architects and engineers have scooped up Autodesk's products. Analysts are predicting that earnings will more than double in fiscal 2004 and increase 25 percent in 2005.

TXU: 175.7 percent -- The energy producer brought in a new CEO in February, and under his guidance, set into a motion a number of moves meant to boost shareholder value.

TXU cut costs and sold off some money-losing divisions. The company also trimmed debt, unveiled two share buyback programs and increased its annual dividend to $2.25 per share from 50 cents (also setting a goal for 5 percent annual dividend growth).

Valero Energy: 92.9 percent -- The nation's largest independent oil refiner was helped by an industrywide improvement in refining profit margins -- unusual during a period of rising oil prices. In 2003, higher oil prices crimped refining margins, and Valero's stock.

Nucor: 97.9 percent -- The nation's No. 3 steelmaker was helped as finished prices in steel increased faster than prices for steel scrap. That gave Nucor, which produces steel by melting scrap, an advantage over its larger rivals such as U.S. Steel, which still make steel from raw materials.

Goodyear Tire: 91.0 percent -- The largest U.S. tire maker improved its business in North America by repairing severed ties with many old clients and dealers. After a long spell of red ink in 2002 and 2003, the company turned a profit in the second quarter of 2004 and built on that gain in the third. The stock is trading near 3-year highs.

Monsanto: 96.9 percent -- The weak dollar has made this agricultural company's weed-killers, bio-engineered seeds and other agricultural products more price-competitive overseas, boosting international revenue. The company's performance last year wasn't so shabby either – its stock rose 49.5 percent in 2003.

Aetna: 86.3 percent -- Cost cutting and underwriting gains have led to strong growth in revenue and earnings; operating income was up 26.6 percent during the first nine months of 2004. Some analysts think the aging U.S. population and Medicare reform can only add to the growth.

Biogen Idec: 84.9 percent -- Investors who bid up shares this year are eyeing good things to come. Tysabri, a blockbuster new drug, hit the market this fall for the treatment of multiple sclerosis, and the company is hoping it will be found effective for treating Crohn's disease. Analysts project that Tysabri, along with Biogen's older MS treatment, Avonex, and its cancer treatment, Rituxin, will drive an eight-fold increase in revenue by 2010.

Starbucks: 90.3 percent -- Will the super-strong coffee ever burn out? The world's No. 1 specialty coffee retailer logged the 13th consecutive year of comparable-store sales increases of at least 5 percent and the stock's jumped 407 percent in the last five years. Net sales rose 30% to $5.29 billion. Net income rose 46% to $391.8 million. In addition, Starbucks opened 1,344 new stores last year to bring the number of stores to over 8,500 worldwide. Analysts and company officials still insist the Seattle-based retailer is years away from saturating the market with its latte joints, and accordingly, Starbucks recently increased projected growth from 25,000 to at least 30,000 stores.