login-lockdown – protect your neck

nextgen gallery – great for internally managed photo galleries

tubepress – let youtube handle the bandwidth and conversion please.

eventsmanager (for RSVP type events)

gigpress (for musician-style tours)

capabilities manager – if you have multiple content editors with varying roles.

Mail From – change the default from email address and name.

exclude-pages – sometimes the main nav doesn’t need to be that cluttered

user photo – great for adding some personality especially with multiple content authors

maintenance mode – show users something professional while testing and updating

shadowbox js / lightbox PLUS – sexy photo/video presentation

advanced twitter widget – meh. it works well for client managed twitter feeds.

Register Plus – get all the info you can from your users

all in one SEO pack – what good is a site if no one finds it

kadom-ads-management – if you have savvy enough admins to manage their own ad space

wp super cache – great for high-traffic sites but can cause issues with some plugins

formbuilder – submits forms via email and to the db. export to csv. nice.

FeedBurner FeedSmith – if you’re into feedburner for rss feed management. This plugin works excellently.