Someone out there made an emulator for i-mode cell-phones. I saw it even mentioned in a google book about mobile game development. The current more available cell-phone emulators only cover J2ME and nothing else...
Well, someone took lots of screenshoots and also posted extensive sprite rips for the Seiken Densetsu remake. However, getting hold of the i-mode emulator and the actual binary images of the applications is next to impossible (and most of them had their official pages removed).
But there's still the Desmume high-res fork, SSF for the Saturn, and a bunch of homebrew emulators working on the GBA and WonderSwan. Someone even bothered to emulate the weird Slide MAG add-on for the DS but for an obsolete emulator (IDeaS) without ever releasing the source.
It's sort of frustrating knowing there's lots of tool-assisted speedruns, game guides, romhacks, homebrews, romhacking utilities, and roms/emulators for i-mode mobile platforms, coming out of Japanese web but actually getting hold of them is next to impossible.