Jin Hua Shan Mazu Folk Museum (金華山媽祖文物館; 9, Lane 119, Guangming Road; tel: (04) 2676-5678; open: 09.00-17.00 Tue-Sun) is a newish privately-owned museum in Dajia District, Taichung City. It was established to showcase Mazu icons and religious paraphernalia purchased by a Dajia-born businessman during trips to the Chinese mainland, and the collection is well worth seeing if you're interested in local religious culture. There are capes, hats and shoes used to dress images of the sea goddess, but the finest object in the collection is a Mazu statuette thought to date from the Southern Song Dynasty (1127-1276); the mineral dyes used to paint it have hardly faded despite the passage of centuries. At the time of my visit there was little in the way of English labelling, but this may well change.
The museum doesn't have a proper website yet, but you can see photos taken inside the museum on this page.