Created by Mr. Paul Rawlings, the UK-based classified listing site Tweebay lets Twitterers to buy and sell their stuff on Twitter. Although it sounds quite familar to the popular online aution and shopping website - eBay, but it has no connection with neither Twitter nor eBay.

To use the service, you need not to provide your Twitter credentials and Tweebay only requires users to follow them on Twitter. You'll then receive a direct message to verify your account.

Buying and selling using this free service is simple. If you've an item to sell, you'd have to provide 240 characters to describe your item and a photo to accompany with it. Your listing will be up on Tweebay and to attract more buyers, you can automatically notify all your followers. To buy, you can confirm your bids via direct messages on Twitter.

Even though this is just a start-up that was launched a few days ago, it already has over 230 users trying out the service.

Drawing mind maps helps us brainstorm and understand much better. As the founder of Buzan World - Tony Buzan explained, "it gives you the freedom to roam the infinite expanses of your brain. The Mind Map can be applied to every aspect of life where improved learning and clearer thinking will enhance human performance."

I know that there are dozens of mind-mapping softwares out there that lets us draw diagrams on the computer or the Web rather than on paper. Today, I'll be focusing on one mind-mapping app called Bubbl.us.

Bubbl.us is a simple and easy-to-use Web mind-mapping tool which lets you brainstorm on a particular subject online by providing state-of-the-art features that many similar products don't have. Besides having the basic and essential feature of creating colorful mind-maps, it also enables you to collaborate with your friends, embed it in your blog or website to share with your readers, email or print the mind-map, and many more.

Using advanced technologies such as Flash, AJAX and Prototype, Bubbl.us comes in a drag-and-drop interface to attach bubbles together and a mousewheel zooming feature to focus on a certain portion. By moving the color slider, you can choose your favorite colors and even alter the saturation and lightness of the color. If you know the hexidecimal color code, inputting it in the box is also possible. You can easily manage and collaborate your mind-maps by accessing the control panel on the right. Since the current collaboration tool only allows sharing with friends, it would be better if Bubbl.us lets us collaborate in real-time with multiple users at once.

This free app is mainly meant for those who need to sort out their messy information and brainstorm for more ideas with the comfort of the computer instead of scribbling untidy words on a paper.

If you're using Windows Live Messenger, you'll know that it'll automatically stores your chat history in your computer so that you can access them anytime you want and find out what you've said a few weeks ago. That sounds quite useful but here's a better tool.

IM History is a desktop app that helps users store their chat history online and allows them to view and access them online on their Web browsers using a one-click access from their PCs. Currently, IM History supports multiple IMs such as AIM, Skype, Windows Live Messenger, Yahoo Messenger, ICQ, Pidgin, Miranda, Trillian, QIP, etc.

Before you IM History records your chat logs, you can upload and merge existing history archives. The impressive search feature enables you to search for chat logs by bookmarks and links, word/phrase or by contact. You can even create a metacontact for your multi-IM chat buddies or edit the contact details.

Using the advanced technology and algorithms in the Snapter software, you can say goodbye to the bulky but useful scanners and welcome the handy digital cameras. Why do I say so? With Snapter, users can easily snap a shot of a document, business card, or even books and it will then transform the camera photo into a perfect scanned document.

Snapter's deceptively simple-looking interface can correct page curvature and perspective, crop, flatten, and process your business cards into a PDF document in just a few seconds. This tool is pretty useful as you just need to carry your digital camera around and snap photos of books in a library, menu in a restaurant, etc.

Currently, Snapter is free to use but when you sign up for premium subscriptions, your outputs will not have watermarks or taglines on them.

Bookgoo is a simple online collaboration tool that lets users highlight and annotate their documents online just like the way you'd mark up a piece of paper with a highlighter and discuss it with others.

To start, simply register for an account and upload your files to Bookgoo. Currently, it only supports formats such as PDF, HTML, DOC, XLS, JPG, GIF, etc. After inputting in your title and description, you can select whether you'd want it to be shared or private if you don't want others to view it.

At the editor, there is a zoom feature which you can zoom the document to view small details. Other key features include adding notes, pencil tool, color picker, email to friend, download it or add to groups for collaboration.