The haunting difficulty.
Malbolge is a well known language among esoteric programming fans. I made Malbolge (from conception to implementation) in one afternoon, which should tell you something about the depth of the design process. - says Ben Olmstead - Malbolge creator.
The specification severely differs from the reference implementation, dividing Malbolge users into even half. The language is based on tenary numbers, again, quoting Ben Olmstead, because it seemed harder to understand than binary.
Everything summed up makes it impossible to write efficiently in Malbolge. The instruction encryption, the crazy-op and tight instruction set aren't helping at all.
Return of the king?
Malbolge isn't Turing-complete by any means - the adressable memory is limited, so in 2007, Ørjan Johansen publishes draft for Malbolge Unshackled, attempting at making Malbolge Turing complete. The output in Malbolge Unshackled requires the A register to hold precise unicode point (!), instead of n mod 256 value.
And then, it all started. Various programs have been made, some of them have been simple, some of them have been complex - the spirit has been kept, until 2048 happened. Upon that point, I simply decided that there's nothing interesting left for me to do in Malbolge, and I have dropped it.
There are plenty of resources on the Internet. I haven't invented many new things, therefore I can't see much sense in explaining every single topic by myself. However, if you would like to know something about Malbolge, or you just want to suggest me something strictly related to Malbolge, please toss me an e-mail.
What do I think about Malbolge?
I really feel teared apart now. Malbolge is pretty much the basic math and code pottery (I really hate it really much) as you start diving into it. There are plenty of tools to make programming less hellish, so the spirit of difficulty slowly, but surely, disappears.
On the other side though, Malbolge has been made to hurt and become impossible to program. I enjoy Malbolge because of it's unorthodoxy and unique approach to programming.