File sharers were the first to rush in. The photo-sharing service TwitPic, one of the oldest Twitter mashups, lets users send pictures to their followers by storing a photo on its servers, then passing the link around on Twitter. Now there are newer apps like Tweetcube and Twittershare, which let users share larger media like MP3s and videos.

Twitter’s limited format of short, text-based announcements are a natural match for sites like TrackThis, which you can use to get status updates on FedEx and UPS packages, and Tweetajob, which job seekers can use to get real-time updates about new job openings.

Anyone who needs help quitting smoking can use Qwitter to monitor their progress. Those looking to lose weight can turn to TweetWhatYouEat or TweetYourEats.

Hardware hackers have put a new spin on the Twitter mashup — as it turns out, just about anything that can be plugged into the internet is capable of talking to Twitter.

Programmer Ryan Rose rigged up his washing machine to send him a tweet when his clothes are done. He just follows his machine’s twitter account (it’s PiMPY3WASH) and he knows when to go downstairs and move his undies to the dryer.

Linux hacker Shantanu Goel set up a video camera and some motion-sensing software on a PC connected to the internet. If anyone breaks into his house or goes snooping through his room, the software detects the movement and sends out a tweet.

Tech-savvy environmentalists can install Tweet-a-Watt, a gadget that plugs into your wall socket and connects to your wi-fi network. Once a day, the pocket-sized device broadcasts stats of your daily energy usage to Twitter.

Whether that sort of transparency results in embarrassment or bragging rights can be determined by a system like the one created by Justin Wickett. The Duke University student wired up his home so he could turn his lights on and off remotely, just by sending a text message to Twitter from his mobile phone.

Twitter Fast Growing Beyond Its Messaging Roots | Epicenter from Wired.com.

Sometime soon, Twitter is expected to unveil its plan to make money. Based on comments made by Twitter co-founders Biz Stone and Evan Williams recently, it seems likely that plan will involve charging companies for accounts with special privileges.

In New York Magazine this week, both Stone and Williams said that charging companies for brand verification is something that the company was looking into. This makes a lot of sense, especially given the rise of fake profiles, like the one that was recently taken down for the Dalai Lama. They note that a paid corporate account could have features like a prompt when a new user joins a company’s feed.

Then today, Stone made similar comments to the UK-based Marketing Magazine. “We are noticing more companies using Twitter and individuals following them. We can identify ways to make this experience even more valuable and charge for commercial accounts,” Stone told the publication. He went on to note that other ideas of charging companies to use Twitter to market products and/or provide customer service were on the table.

The latter part is something which companies like Zappos and Comcast have been doing for a while. They have employees that scan Twitter (something much easier now with Twitter Search) to see who is saying something about their company. If it’s something negative, or there is some kind of problem mentioned, these Zappos or Comcast Twitter users send messages to the user having the problem. I’ve experience this first hand with Comcast’s Twitter rep, Frank Eliason, who tweets from the account ComcastCares.

Marketing products on Twitter is a potentially more interesting idea from a revenue perspective. Late last year, Dell reported that it had made over $1 million in revenue thanks to Twitter. More recently, Dell announced that it would start offering deals exclusively to users who follow its accounts on Twitter. With Dell using Twitter to spur sales and clearly making money off of it, it makes sense that Twitter should be getting some of that. But the question of how much, is a tricky one.

“If it becomes complicated and costly, our instinct would be to move elsewhere,” Bob Pearson, vice-president of communities and conversations at Dell told Marketing Magazine. Other companies Marketing Magazine asked about the idea of Twitter charging businesses to market on its service, said similar things.

This idea of charging for corporate accounts, has been around since at least October, when CNET reported it was hearing whispers about such a plan. Since then, we’ve heard the exact same thing from a few other sources. In November, Williams started to float that idea out there publicly. But now, with talk about this plan clearly picking up, I think it’s a safe bet that it’s coming sooner rather than later.

Twitter has raised over $20 million in funding. Recent reports suggest that it’s looking for another $20 or so million, which could push its valuation close to a quarter of a billion dollars.

Twitter starts to talk up the charging companies plan » VentureBeat.