As others have said it is best if you go looking.
Still
Are you any good at GUIs? Some seem to really struggle with the command line and many a hacker types will make something and leave it as a command line only tool. Worse still it might need 10 different command line tools, all doing relatively simple things, to accomplish a desirable thing for end users. The really low level stuff is usually done by the sorts of people that know electronics, read the likes of
http://problemkaputt.de/gbatek.htm for fun and could probably go pretty far in designing their own device with what they already know but there is plenty that a decent UI maker can do.
Or if you prefer there are maybe 8 patching formats in common use in consoles if you could incompatible versions (IPS, UPS, a couple of versions of xdelta, bsdiff, a couple of versions of PPF, and a few more obscure ones). There is no universal patcher, never mind a graphical one, despite most of those being either trivial, open source or otherwise well documented, neither is there a patcher for android devices for most of those formats.
Speaking of (ROM) hackers.
I must have pulled apart hundreds of games and thousands of formats across multiple systems. I do make an effort to document and share as well.
Number of tools I have made that allow someone else that does not care to make their own/do battle with a hex editor to edit. 0. I am so very far from unique in this.
Even the tools that do get made often find themselves really buggy and hard to use -- pick any ROM hacking section anywhere on the internet and you will find people complaining about quite serious bugs that would be fairly easy to squash if someone took the time. If you want to help people make viewers and conversion tools for their favourite games or formats they use then you will make friends very quickly.
The DS is one of the most extensively hacked systems ever produced, I am not aware of a single tool that will relink files within its file system. The UMDgen tool for the PSP had relinking functionality for years and the concept was well known too as many hackers did it by hand.
So yeah if you can do something there, which is very much in the realm of C# and the other parts of the C family you know, you will have no end of choices for things to do.
Not many emulators are written in c#, but c and c++ would be most of them (they are high performance code after all).
You don't have to get in and start debugging the cores to make them that little bit faster or more accurate as there are usually endless choices of things to do as far as making memory/graphics/sound viewers, improving cheat finding, improving the UI, making filters, add nice features like video capture, adding options for it to be controlled by lua (
http://www.fceux.com/web/help/fceux.html?LuaScripting.html ) and all the other things the main emulator dev will get around to doing once they made it "accurate" or faster.
If you can't find something code skills would help with around here then you have clearly not been looking.