Ok so when I first read about this I thought "and why would I care about taking a backup copy of my tweets?".
But curiosity took me to the Tweet Nest website. Note they don't even have the domain tweetnest.com – the url I was led to was www.pongsong.com/tweetnest – weird!
But anyway! So Tweet Nest provides "browsable, searchable and easily customizable archive and backup for your tweets". The website asks you if you ever wanted to take a "look back" to see what you tweeted "this time last year" or if you were looking for a "hilarious video" that you can't find anywhere anymore.
So basically you can install Tweet Nest on your own web server and voila, you've got the ability to save all that crap you tweeted about and some!
Here are the highlights of Tweet Nest
Back-up & Archive: Basically store and search tweets to find whatever you are looking for. Includes the ability to search for Retweets and links to original tweets. All your tweets going back in time can be backed-up.
Viewing: You can view all tweets at a glance and they will event include Twitpic and other media hosted on various media app providers. And you also get an "elegant" bar chart of the number of tweets, retweets, and replies you've sent per day.
And wow, you can customize your "archived" tweets to make them look "COOLER"!
For those of you who thrive on technical mumbo-jumbo, Tweet Nest is a PHP and mySQL app running of course on a Linux box.
So, excited about storing your archived tweets and customizing them to make them look Jazzy?
Me too (not)! But hey if it makes you happy, who am I to judge! LOL