The DS still is home to a robust homebrew scene, as we see here in this Portal port that modder Smealum has been working on for about the past six months. "Still nowhere near playable," he writes under the latest video, but it's brought along Portal staples like turrets, cubes, switches and energy balls.
"This is still extremely early footage so please don't be too harsh," smealum writes. "Lots of debug features are present, including the ability to fly, see portals through walls and move cubes from a distance. Also, keep in mind this was shot in an emulator which provides good but still less than perfect rendering. As such, be aware that most (not all, but still) of the graphical glitches you can see in this video don't happen on hardware (mostly the portal transition is a lot nicer on an actual DS)."