for shopping lists. Free and simple. Viigo
for RSS news feeds. Free and simple.
I also highly recommend the REXwireless
products like ToDoMatrix and IdeaMatrix. They're expensive but powerful apps for professionals. Additionally, there is a free white paper on the site called BlackBerry Task Management Best Practices (lower right hand corner of the ToDoMatrix area) that everyone should read, whether they get the Rex products or not.