How to run debian-mipsel applications in Dingux (or everything you kinda need to know to port some stuff but were afraid to ask)

Thanks to Batman52, some of the arcane wizardry behind porting apps is mildly demystified by this most excellent tutorial: http://a320.freeforums.org/how-to-run-debian-mipsel-application-on-dingux-t895.html#p7408

Go on, take the red pill!