Google Earth for, well for pretty wink
PlainText a great simple text editor with DropBox support
PDFpen great for viewing/annotating PDFs
Pages/Numbers/Keynote great demos for how impressive iPad apps can be
GarageBand another Apple demonstration of the peak of app development
Abobe Ideas the best idea sketching app I've seen
iBooks/Kindle for book reading
Byline an RSS reader with Google Reader support, my favourite of the ones I've tried
Instapaper for offline reading of web pages
Flipboard for a unique way to consume Twitter/Facebook etc
Handoff a quick easy way to send web pages from your desktop browser to the iPad
ShopShop a great little shopping list app
iTunes U
StarmapHD
Paper best drawing app
Calvetica for a different take on a calendar app
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Remind me to change my signature to something more interesting someday