I would love to see a save state feature in dosbox. This is common in game emulators for consoles so I think it would be easy to "borrow" the coding techniques from some open source console emulator and apply it to dosbox.

dosbox is primarily used for games and quite a number of old DOS games do not have save states. Using save states is a big part of the gaming culture - people swap save states to quickly view alternative endings or to gain power ups (ie: cheating). Save states are just another function that adds to the experience of a game. With so many games to play and the list expanding, many people find that using save states enables them to fully experience more games without the time investment that would normally be required.
It also helps people who do not have the skills necessary to beat a game.
Im sure that there are multiple opinions on this issue and many people will bring up the "I don't cheat" argument. But it is a fact that save states are well implemented in console emulation and I think it would certainly be another useful feature for PC DOS emulation. I would also like to add that it seems like a waste not to implement extra features into emulators when they are relatively easy to code in. Snes9x, finalburn, project64, etc... all well known emulators with save states.