Wikipedia.org: The text at this reference site could be a tad bigger, but what's genius about this site is how it uses show/hide buttons in its articles. This lets you see very quickly the type of information available for whatever you're looking up, then see just what you want. So you get the whole article, but don't have to wade through all of it to find what you need. Note that Wikipedia's home page is not mobile-friendly, but if you go to specific articles from a search engine, those pages are mobile-optimized.
MLB.com: It's easy to follow your favorite teams on the Major League Baseball mobile site, though the stats are a bit buried. But it's a much better experience than NFL.com, NBA.com, and NHL.com, all of which are too dense and hard to work with on a mobile screen, or Sports Illustrated's SI.com, which is complete but a little hard to read and navigate.
Amazon.com: The people at the online shopping site have a great iPhone app that makes it really easy to shop. But they also have a great mobile Web site that lets you check your cart and orders, as well as shop. It's an impressive example of how to simplify a complex site without losing its richness or functionality.
AA.com, Delta.com, and JetBlue.com: These three airline sites all seem to use the same template, except for color schemes. They're not fancy, but they are good examples of straightforward service sites that let you check your flights, book a flight, or do other basics when on the go.
MercuryNews.com: Many news sites use a disappointing technology called mDog that essentially delivers an RSS-style list and usually strips out graphics. The San Jose Mercury News' site is more like an iPhone app in that it uses menus and offers functionality like search -- plus displays the content -- in a very useful way. (Full disclosure: Like most tech-article sites, InfoWorld uses the dreaded mDog as the default for mobile users, but you can get our beta optimized mobile site at infoworldmobile.com, if you're coming from a modern mobile device. You can compare the two from a desktop browser at the InfoWorld Mobile page.)
WellsFargo.com: Bank of America has a good iPhone and Android app, but its Web site is not mobile-friendly. By contrast, Wells Fargo's banking site makes it easy to do basic banking from any mobile device -- it's simple but not dumbed-down, and oriented to getting tour transactions done quickly. Wells Fargo also offers an iPhone app, but note the alleged Wells Fargo app in the Android Market is a scam.
Make no mistake: There's a place for great apps for your favorite mobile device. But any site useful for people on the go really should offer a mobile-friendly version, so you're not confined to any one mobile platform. Let these examples lead the way.
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