Ok so...
Summat
Nowt
etc, all fine as they are more accents/dialects
Sumink
Nuffink
everfink (without the Y)
Not fine, not fine at all.
Amblumance as said by my very intelligent (ex) friend because the guy she fancied thought it was cute, about as far from fine as you can get. Mainly because he was my BF who dumped me for her. She then did the same trick on his brother, oh how I laughed :o