Hard to say.  I'm into several art forms.  Lately it's been 19th-20th century Japanese prints.  Composition and color is amazing.  I really like realism and Escher's work, probably one of my favorite artists ever.  I've always been into realism painting with oils so from say 16th century to the late 19th century.  I'm not a huge fan of contemporary abstract, but I do love it when painters incorporate abstract color and stroke expression into either a landscape or figure painting.  When done well with human figures it's rather stimulating.