Tumbl.in lets you stumble upon links in your Twitter timeline, favorites and lists

Every once and awhile, you stumble upon (get used to that reference), a service so simple and cool that you ask yourself right away, “Why didn’t I think of that?” Well, Tumbl.in is one of those services.

So what is Tumbl.in? It’s StumbleUpon for links in your Twitter timeline, Favorites and maybe most importantly, Lists – and it’s brilliantly done.

As we said, it’s dead simple too: just go to the site, login/give permission to the app with you Twitter credentials and then you’ll see a screen like this where you can choose where (your timeline, Favorites and/or any of your Twitter Lists) Tumbl.in will look for links to show you as you tumble/stumble upon (see, we told you to get used to it):

You then save your preferences (you can go back at anytime to change them) and then you start tumbling. Just like in the video below. Brilliant idea for an app, well executed in a straightforward manner, and as all you’re doing is tumbling/stumbling through a curated people/lists that you’ve already chosen to follow, you get a kind of personalized StumbleUpon that quick, timely and most importantly, relevant to you. With well curated Lists, Tumbl.in could be extremely useful to quickly find really interesting articles, images and videos. Take a look at the video and then go ahead and check it out yourself, we doubt you’ll be disappointed.