The following are Greasemonkey (if you're using Firefox) and TamperMonkey (if you're using Chrome) Javascript scripts.
They alter the content of the page you're on in some way, whether it be by changing colors, positions, sizes, of parts of the page, or whatever.
Anyway, here are my scripts.

Tumblr Sponsored Posts Hider v1.2
Hides sponsored posts in the Dashboard, Radar, tags, and Spotlight. If you come across another place where sponsored posts show up, email me or send me a message on my Tumblr or something.

Tumblr Annoying "ASK ME SOME OF THESE QUESTIONS" Posts Hider v1.2
Hides those giant Chat posts where people beg for empty gestures of acknowledgement that look sorta like:
1 - My favorite color
2 - My last meal
3 - My dog's name
4 - My greatest fear
5 - My leastest fear
etc.

Tumblr Multiple Tag Browser v1.0 (Chrome works fine, maybe Safari too, only occasionally works in Firefox)
Allows you to browse multiple tags on Tumblr. Let's say you want to view pictures of cats, dogs, turtles, and Solaire of Astora.
You'd go to the url: http://www.tumblr.com/tagged/cats,dogs,turtles,solaire of astora
So yeah, pretty much just separate the tags you want to see with commas and the script will do the rest!

Being that these are just simple Javascript files, they're entirely open-source (the way code should be) and free to be used for your own enrichment.
Thanks. If you have any requests for features that the Tumblr staff are too dense to add, please send them my way and I'll get right on them!

Current Works in Progress:
-Tumblr Enormous Vertical Photoset Shrinker for making those giant photosets that take thousands upon thousands of pixels on your screen much smaller and more convenient to scroll past.
-My visitor tracker (almost done)
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