[nitemice]

Unless I've misunderstood, you can use splits to show multiple buffers in Vim without any plugins.

[billfruit]

What about manipulating of splits, like converting vertical split to a horizontal split, enabling/disabling synchronized scrolling, etc..

[logram]

You can do both of those things in vim. I don't mean to be nitpicky, I'm just mentioning in case someone reading this didn't know and uses vim. You can set scrollbind and convert splits (off the top of my head I think it's Cw Ch and Cw Ct).