By default, if you click the "Gmail" in the upper-left corner, and select Tasks, you'll get a pop-up window in the bottom-right corner with the todo-list.
It can be minimised, but then the tasks aren't visible, which makes it less useful. Keeping it open is a problem, because it blocks a part of the Inbox, and just gets in the way visually.
Is there a way to have the "Tasks" list, or something like it, but which fits into the sidebar on the left, under the menu, i.e. as an alternative to the Chat list?
Best Answer
There is actually a way to display this very same Tasks gadget inside the sidebar, rather than an overlaid window.
Settings > Labs > Enable Add any gadget by URL
Go to Gadgets tab and enter the URL
http://www.google.com/ig/modules/tasks.xml. Click Add.Done!
Reference: http://www.keanei.com/2011/11/04/adding-google-tasks-to-the-main-gmail-window/