I have a problem. And so do you.
I spend too much time on Facebook killing monsters and tending to my farm that I've become unproductive. I spend too much time tweeting about inane things (E.g. "My jeans smell", "I forgot to rinse the shampoo off my head again" or "I am awesome") that I've become less efficient. I spend too much time on forums reading things from idiots who can only say nice things about Sammi Cheng, and would rather die than to admit that Sammi Cheng is/was fat.
Think about it some more and you'll realize just how many hours of your life you've wasted away, when you could be doing something much more worthwhile. Like picking your nose.
What I've got today is a script that would block websites of your choice until a certain time of day when you can use it without feeling guilty. This isn't a parental block program but rather a self-induced barrier between you and Facebook (for example). The script's called Invisibility Cloak, developed by Gina Trapani from Lifehacker.
You need Greasemonkey and Firefox installed for this to work.
Click to install Invisibility Cloak script
By default, it has flickr and metafilter blocked and the release time set at 3pm. Release time being the time when all blocked sites are unblocked.
Quite simply, this script "cloaks" the site until 3pm when work is almost over and you feel you can relax.
The release time can be changed: "var surf_time_after = 15;" with 15 being 3pm. Like military time. The cloak is off on weekends. You can see from the picture above, I've changed mine to unblock at 4pm.
To change the release time (after installing the script), Tools > Greasemonkey > Manage User Scripts > Invisibility Cloak > Edit (beside the "Enabled" checkbox) > If it asks you to pick a text editor, go to C:\Windows\notepad.exe > Look for "var surf_time_after = 15;" and change the time accordingly > Save.
To add pages to the block list, Tools > Greasemonkey > Manage User Scripts > Invisibility Cloak > Included pages > Add.
The asterisks (*) are wildcards, in case you didn't know. E.g. http://*.cheahwey.net/ means all subdomains from this site will be blocked, like mobile.cheahwey.net as well as www.cheahwey.net.