Visions of Frank: Short Films by Japan's Most Audacious Animators

Collection of short animation with various animation styles, techniques and story genres. Some of the shorts get so weird it earned the anime dementia genre. 

Anthology of short anime with various arstyles and animation techniques made by different people. 

Bizarre, obscure and unique pieces of animation with dark themes. Both cult classics in their own way, in my opinion. 

Collections of short movies with different visual styles and themes, movies which some of them can get quite weird. 

Anthologies of various short anime made by different people with different animation techniques. Those shorts have unusual feel and not style that you would usually expect from anime. 

Collection of short artistic animations made by different artists with different animation styles and techniques. 

Collection of short stories with same central theme. Multiple various artsts contributed to this anthology and each segment has unique animation style, including lot of experimental animation techniques. Both are more pieces of art than an anime. 

Both OVAs are anthologies of short stories made with various animation styles and techniques.