Back in 2000 Jakob Nielsen stated that "About 99% of the time, the presence of flash on a website constitutes a usability disease." Harsh words that have managed to tarnish Flash's reputation even today.
Luckily those who know better realised a while ago, that flash is a powerful tool whose purpose extends way beyond animated splash pages. Macromedia's latest Newsletter features a great case study on how IKEA have used flash to drive their sales, by creating an interactive kiosk for their stores.
Another website that utilizes flash in an inspiring way is TAZO Tea. The site is visually gorgeous and interesting to browse through, even for non tea drinkers like myself.
The one thing that I often mention to clients is that using flash doesn't mean that the entire site has to be built using flash. Flash should be an invisible technology used to enhance the user's experience. The Westin Hotel uses flash to create lovely emotive promotions on the home page, tt's subtle yet effective.
Another great example is the Mini website, it allows users to create their ideal mini instantly. Actually many auto related websites are using flash in very clever ways to show case their products.
My all time favourite is Nike every new website that they release is beautifully designed. With the use of imagery and animation they capture the essence of Nike even before they display one of their products. There are thousands of examples out there, I think its time for people to put their negative opinions of flash behind them and see it for what it is.
I guess it all comes down to one thing; use it wisely and it will enhance the users experience. Oh and don't believe everything you read Jakob Nielsen may have done a lot of good for usability online but he has also influenced many people to follow unnecessary constraints.
Other articles of interest :
Macromedia’s Top 10 usability tips for flash web sites