Module development and code questions

It seems pretty easy from this vantage to write an calendar module expressly for users. That is, any event a user adds to the calendar is only viewable to the user who wrote the event. I don't see one, so I'm wondering if it's more difficult than I believe. Does anybody have an opinion about this?

Drupal 4.7.3
theme channel_nine dramatically modified (kept the 4 columns, though)

Is there anybody who could help me to resize my div #center box to , lets say height: 500px; width: 100%; and add a scroll bar only on this div #center box.

When i add this code to my css stylesheet, it resizes the body allright but all the data that would have made the box stretch down is being cropped off accordingly to the resize values.

i want to have a page like download page in drupal.org but i don't know what is this module. Anybody can so me what is this module and where i can download.
Manythanks

i want to find a module that display news like some e-newspaper website such as: http://vnexpress.net
News is display in category and have a page to display all news's category, in each category will show a tease of 1 news. Anybody can help me?
Manythanks

I'm writing a filter for an input format, and I want the filter to know the number of the node in which it is stored. I know I can check the arguments with something like:

if ((arg0=="node") && (isnumber(arg1)))

but when the filtered text appears in a teaser on the front page, the arguments don't reflect the node number.

Any suggestions?

I would like to develop a possibility to give access to content based on the duration of each users membership.
So that a user who is registered 3 month can see more content than a user who is in his first month.

1) This would require to assign a specific timeframe (for the required duration of membership) to each piece of content.
2) And it would require a function that then checks each users time of membership when he logs in. Then he would be allowed to see the content that is assigned to this timeframe/duration of membership.