Let’s face it, Internet is addictive. Sometimes, we land up in some social site like Orkut, YouTube or MySpace and end-up spending countless minutes of productivity. Of course, we can multitask, but multitasking just makes it a lot hard to remain focused. Distraction can still steals your focus and make you less productive.
My brother, Jeethu, pointed me towards a super-handy greasemonkey script called Grindstone. It helps you remain focused on your important tasks by blocking websites which eat away your productivity. You block websites for certain period of time. For instance, you can configure Grindstone to block YouTube.com for ‘x’ number of minutes, visits or during business hours (9am to 5pm). 
There are similar add-ons for Firefox like LeechBlock or PageAddict, but I personally prefer Greasemonkey scripts over add-ons because of performance issues caused by installing lots of add-ons. The developer has put up a 60 second quick screencast, check it out.
You’ll need to install Greasemonkey add-on for Firefox 2 or 3 before installing this script.

wrote, on June 10th, 2008
How easy are the pages to overide. I mean, if you change your mind, can you use admin rights to allow access to a page or site?
If so, doesn’t it just come back to willpower!
wrote, on June 10th, 2008
That is a really handy script. Greasemonkey is one of my favorite FF add-ons. Simple yet powerful.
wrote, on June 10th, 2008
Awesome little script. Can one apply it to staff pc’s so as to prevent them from accessing facebook during business hours?
wrote, on June 12th, 2008
@SEO ..
hehe .. u seem a pretty hardened employer
wrote, on June 19th, 2008
@SEO
You will never be able to completely block facebook, myspace, etc from your employees. Proxy servers and web proxies are always present!
wrote, on June 21st, 2008
pretty and simply awesome..Thanks bose
wrote, on June 26th, 2008
@Fahad, our IT boys are pretty hot, they have installed something called Websense. If you try and bypass via a proxy, it just kicks you off. Not sure how but very annoying!
wrote, on July 8th, 2008
@Wii
Hmm, I will search for it on the net. Lets see what it does.