Aloha!

This is the BRD-MC-CSS- Cave Spider Spawner.

Not too special or new but still fun to use.
This build has 2 versions- 1 for XP and the other straight to drops.
Both versions have the actual spawner suspended in the center of a tinted glass room that has a water flow floor and subfloor that pushes the drops either towards your waiting crystal sword or soul fires. Both are equipped with Redstone On/Off systems. When ON- the Redstone lamps are turned off to allow spawning and when OFF- the lights are on to prevent spawning.

A custom version of this build is included in a world build located here:

Pasting: You are faced south- Up against the front (has chest) left corner at ground level. Each version takes 11 blocks wide, 11 deep, 13 tall.

Remember to paste redstone asynchronously using methods like Carpet or Fastasynchworldedit. Pasting in tick time presents immediate block updates upon paste among other anomalies that break redstone builds.

I hope you enjoy!