Just thought I would share a seed that I have really been enjoying. It has extreme hills by lots of water and mushroom islands galore. The seed is 107994. Not sure if its been on here before or not. I have only found a few things in the spoiler. Drop a line here if you decide to check it out or if you have any more questions.
A surface dungeon Zombie spawner with a bit of iron and iron horse armor at x -149 z -244
A zombie spawner X -73 Y 14 and approx Z275 I don't remember what was in it possibly a saddle.
I put a Nether Portal on the water at x -22 y 64 z 383 and ended up right in a Fortress next to Nether Wart.
A minecrart with melon seeds X 13 Y 14 Z 513
A swamp biome at X -220 Z 700
Another swamp biome at X 266 Z383 which always seems to have a brown sheep. There are a couple more Mushroom Islands if you keep following the X to the positive from here.