Here are 6 tips for those people who like to know their way around Facebook.
Underline or bold a chat message:
You can underline or bold any chat message by either adding a * or an _ to the beginning and end of a chat message.
Bold Message –> *Bold Message*
Underline Message –> _Underline Message_
Using more than 420 words in a status update:
You can easily overcome the 420 word limit of status updates. All you have to do is upload a picture and then you can write without any limitations:

Breaking the Limit
Show post from all your friends:

Show posts from all friends
Did you notice that only a limited number of your friends appear in your News Feed? The reason is that not all your friends appear in News Feed by default, only the ones that you interact with the most appear there. To adjust that, you will have to go to News Feed–>Most Recent–>Edit Options–> select ‘All of your friends and pages’. Also, you can hide any annoying individuals by naming them under the “Hide Posts From” section.
The Facebook Directory:
Everything from people, application, pages or places listed in alphabetical order you can access it all on the Facebook directory.
Extra security for your account:

Protect your account
If you are worried about your account being compromised, you can enable a feature on Facebook that will inform your through an email or an SMS whenever a new location logs on to your account. To enable this feature: go to your Account–>Account Setting–> and select ‘Change’ on Account Security and then check the medium you would like to receive your notification through. It’s also a good idea to enable the https browsing to protect your self from account hijacking attacks.
Download Your Facebook:
While in the past you had to rely on 3rd party services to backup your Facebook information, videos and photos you can now do it from Facebook as well. While you shouldn’t go ahead an cancel your backup accounts because this feature is only available as long as you have access to your Facebook account, it’s still useful to have a copy of the data as well, just in case.
So to download this information go to Account –> Account Settings –> Download –> Learn More. It will take Facebook sometime to gather your information, pictures and videos and when its done it will send you an email providing you with a link to download a zip archive (.zip) of your Facebook account. This archive does not included photos uploaded by your friends that you are tagged in, or your friends email addresses but it’s better than nothing.
Have you found the tips to be helpful? Share with us your thoughts in the comment section below.
I didn’t know about many of these! Thanks for sharing them :)
Boldening and underlining words in status updates would be cooler. Who uses FB chat?!?
your underline and bold type trick didn’t work with my fb, dunno why