Sort posts in the Loop with links in the Sidebar

I would like to have links in my sidebar.php that will “sort” the posts that show up in the loop in index.php.

Basically I want a list of “sorting” links in the sidebar called “Recently Modified” , “Recently Added” , “Sort Alphabetically” , etc. I would like to be able to click this and have the loop populate with posts that fit the criteria.

Make sense?

I feel like this is out there somewhere already, I’m just not sure how to link a word in the sidebar.php and have that link call a function that them shows up in index.php.

Any help would be appreciated. Thanks!