So there are many dialects of Japanese around the country, the ‘standard’ Tokyo/Kanto dialect and humorous Osaka/Kansai dialect being the two most recognized.
Some nifty Kansai-ben (as it is known in Japan) phrases I’ve heard:

なんでやねん (nande yanen) – What the heck?
ちゃうちゃう (chau chau) – No, no (that’s wrong)
ほんまや (honma ya) – No kidding/ That’s true!
あかん (akan) – That’s bad!

There are many other dialects around Japan, if you’ve heard of any/know some cool phrases let me know!

じぇじぇじぇ（Je Je Je）- Used when you are surprised or impressed.
by あまちゃん (Japanese tv drama!)

There are several dialects in Japan. Given the island’s long history, the mountainous mainland that acts as a natural barrier, the island’s seclusion from all exterior events until the late 19th century, and the internal isolation of the various shogunates, the development of so many dialects should come as no surprise.