Chingadera is mostly used to express fustration at something that doesn't work right. It's akin to saying something is a "piece of junk" or when a situation is fucked up, etc.

thingamajig would be "chingaderita" diminutive of chingadera.

Something or someone cool is refered to as "Chingón" or ”Chingona" a wrestler could be named "el chingón" but it's too broad and over used, kind of lacks personal character.

Edited to add:/the meaning of being chingón /a is to be really good at something, not only cool.