Just go to the site and use your Twitter account login to get started. Then you're prompted to upload your document. Choose it on your hard drive and send it up. TweetCube will send it as a short link to your Twitter account with the text you want in the Tweet.
Sticking just with real estate, you could be sending out current market alerts or reports. Or, maybe your county commission just adopted a new rule or code item related to residential construction. If they've published the item as a PDF on their site, as many do, you can download it, then send it up as a tweet with TweetCube.
If you're into community service blogging as well, then there is so much more opportunity to make use of this service. I have local artists and business people that send me emails regularly with brochures or event notices attached as documents or PDF files. I just go to TweetCube and send the document up with my comment.
Micro-blogging with Twitter is a hot topic right now for real estate professionals. I already have all of my blog posts going there immediately, so taking the link to the post will get them to my more extended commentary and the document. However, some may not be inclined to take two steps to get what they can in one. So, for really juicy or breaking news, I can send the document up right away with TweetCube, leaving the blog post with more extended commentary until later.
