We pointed to an iGoogle interface for Google's Tasks to-do manager yesterday that gave users a pretty big view inside their custom home page. Want a totally full-size Tasks view without launching iGoogle? Bookmark the "Canvas view" page.
Google Operating System provides the magic link:
Make it a bookmark, open it in its own tab, and you've got a much more manageable system for completing and adding items to multiple lists. Using Google Apps? Replace the /tasks/ portion with /tasks/a/your_domain/. It remains a mystery why Google doesn't just add Tasks to the "More" button on Google app pages, but this is a fairly good work-around for now.
Fullscreen Google Tasks [Google Operating System]