Web applications aren't the next big thing, they're the current thing.
A web application is just a website that connects to a database in order to do dynamic things.
Every time you buy a product on-line, do on-line banking or even login to a site you're using a web application. The concept isn't really that new these days.
Of course, web applications aren't limited to just logins, banking and selling things.
Facebook, twitter and email are web applications.
There are some incredibly-clever things that can be done with a database and a user interface.

The strength of the internet is that anyone who knows a web scripting language and how to use it with a database can essentially rent a server and start up tomorrow.
Why sell your product from a retail location when you have to commit to rent and rates that are likely in excess of £30,000 for a year when a few hundred pounds on a decent web application, a £5 domain name and £5-a-month on hosting will let you sell?
Obviously you'd struggle to get hundreds of customers on day one, but your costs are far, far lower.

Although not every type of company really needs a web application, any company that is in the service sector should really allow you to book an appointment, meal or other service they provide on-line. Not doing so is a wasted opportunity on their part. Obviously, the same goes for anyone selling any item of value.

Sure, it's way more expensive to have a web application than a purely-HTML site, but unless your customer base is tiny, it should pay for itself somehow.
I think most consumers expect more functionality than just a site that tells them about your company these days, anyway.
------------------------
Khalid.

I'm blunt when critiquing websites and ideas on this forum. The public won't sugar-coat their opinion about your offering, so there's no point in me doing so.

Web applications are the current thing and they have taken over without most people realising . Most sites these days are running some form of script in the background.

web applications are set to increase in both function and popularity look at how much you can do with just an internet connection and a browser
------------------------
web design blackburn | web hosting blackburn | web design lancashire

Proof of what a cutting-edge web application can do:
http://www.youtube.com/watch?v=fyfu4OwjUEI

It's a very old game, but Google have managed(during some employees' 20% time, 1 day-a-week where Googlers get to work on something of their own choice) to take the video game Quake 2 and port it to the browser.
They achieved this by using HTML's Audio and Canvas tags, LocalStorage, Javascript and other technologies.
------------------------
Khalid.

I'm blunt when critiquing websites and ideas on this forum. The public won't sugar-coat their opinion about your offering, so there's no point in me doing so.

cloud computing, but i'm afraid britishcoder would flog me and tell me it's another current thing but i am thinking that if google gets its way, we'd all have no need for desktop applications and just do everything on the cloud.
------------------------
Keyword Rank Checker | Video SEO

It's current, but evolving, to be fair. We're moving in that direction, but not there yet.
Salesforce started this in a big way in 1999 by offering CRM(customer relationship management) software over the internet for a monthly fee. Up until then it was always a boxed product with a fixed cost for the life of the license.

This new industry, SaaS(software as-a-service) ultimately brought about things like Google Apps.
Not everything should be in the cloud yet. We need faster, more reliable internet connections for example before we should think nothing of streaming all HD-quality video and abandon all our blu-ray discs.

It is a good idea, though. Having to rely on our desktop hard drives and updating all of our own software manually and buying it on DVDs is madness.
Storage is cheap enough for the giants like Google, Microsoft and Amazon that it makes sense to have our software automatically-updated for us.
We have the inventor of the relational database to thank for all of this.

As an entrepreneur, the cloud makes total sense.
I'm currently learning a programming language and (very, very) slowly building a SaaS product. My product will replace a lot of desktop software, allowing my future customers to access the type of data I'll be storing from any device that has an internet connection and a web browser. It allows me to develop this software without a team of programmers and, more importantly, to deliver it over infrastructure that I rent for a very low price.

By only paying for those resources that I need, I don't need an investor, or a bank loan.
I develop the software myself and pay $50 in the first month for the data transfer, storage, backup and processor time I need. If my business succeeds, I pay more next month for more resources. It scales up to what I need.
If I fail, so be it. It's cost me a few months hosting and a domain name to go back to the drawing board.
------------------------
Khalid.

I'm blunt when critiquing websites and ideas on this forum. The public won't sugar-coat their opinion about your offering, so there's no point in me doing so.