For those of you that use Balsamiq Mockups, here are a bunch of templates I created that you might find handy.
Download them all in one ZIP file (90KB).

I find myself re-using many of these elements when I design applications (especially the boring/tedious/must-have features, like Forgot Password, Sign In, 404 page). Enjoy!

The following mockups are included in the ZIP file:

Home Pages

Home Page, Members Only Mockup
Home Page, Downloadable Product Mockup

Feature Tour

Feature Tour Mockup

Pricing, Upgrade, Downgrade

Pricing Page Mockup
Upgrade & Downgrade Mockup
Upgrade “Thank You” E-mail Mockup

Read-Only List of Items

Read Only List of Items Mockup

Editable List of Items

Editable List of Items Mockup
Add Item Mockup
Edit Item and Delete Item Mockup

Invite Friends

Invite Friends Mockup
Invite Friends Via E-mail Mockup (Popup)

Settings / My Account Page

Settings / My Account Page Mockup

Sign In

Sign In Page Mockup
Sign In Popup Mockup

Forgot Password Process

Forgot Password Page Mockup
Password Reset Email Mockup
Reset Password Page Mockup

Miscellaneous

404 Page Mockup
Log / History Page Mockup
Downloading Page Mockup
Windows System Tray Mockup
Windows Tour Mockup