i love the admin bar i wrote a blog post about the best ones http://www.loadedarticles.com/blog/blogging-tools-and-widgets/
Sitemap generator, AutoUpgrade, AutoBackup, AllInOne SEO, and FeedFooter. The first thing I do after a WordPress installation is pop in these plugins.
All in One, is a genuine must have, no one will disagree. Besides that I like WordPress Stats and my readers like recent comments. They monitor it to switch between posts to comment
All in one SEO, Simple tags, Sitemap gen, post views, useronline, super cache, etc and so many more...
Here is a great list of traffic widgets and plugins you could easily add to your blog. widgetsforfree.blogspot.com/search/label/Traffic
All in one seo, i love it, mostly the plugins ive installed so far have been for seo and practical reasons.
Thank you MeetHere, I found two new plugins to add thanks to your post. I have listed the plugins I use HERE.
My favorite plugin is Social Bookmarking. BTW thanks MeetHere for sharing top wordpress plugins with us. DON.