Ayman

With this plugin you can time limite the users accounts registered on your website for a specific amount of time.
The status of each account is displayed in each user profile which includes: 
1. Account status 
* New User The user didn’t login since the plugin is activated 
* Activated The user has logined in and the account is not expired 
* Deactivated The account has reached the time limit 
2. Account activation date 
* 0 The user didn’t login since the plugin is activated 
3. Account expiry date 
* Will show the date on which the account will expier.
Any user with “edit_users” capability can activate and deactivate each user account by clicking on Activate/Deactivate links under each user.
In the options page you can: 
1. Specify the accounts time limit 
2. Insert a custom error message for expired accounts

Time Limited Account

With this plugin you can time limite the users accounts registered on your website for a specific amount of time.

pishmishy

This plugin compares a list of passwords against the user accounts in a WordPress blog, using the password hashing functions built into WordPress. It can be a useful tool for auditing your user’s choice of passwords. This plugin uses no functions or data not already available to other plugins, or administrators.
<h3>Getting Help</h3>
E-mail james@freecharity.org.uk

WordPress Password Cracker

Audit WordPress user passwords against a dictionary file.

Time Limited Account vs WordPress Password Cracker