This table demonstrates how individual codepoints render with either the vrt2 or vert OpenType features enabled in the case of Firefox 4 and above, or how it renders with a vertical writing mode enabled in Microsoft Internet Explorer or in Webkit Nightly. Chrome rendering of vertical text is wonked, I wouldn't bother.
The table uses four fonts, Hiragino Mincho (OSX system font), Kozuka Mincho (Adobe font), Meiryo (Windows system font) and MS Gothic (Windows system font). The set of codepoints used is the union of codepoints supported by the first three fonts. Only MS Gothic lacks support for the vrt2 and vert features. If a font lacks a glyph for a given character, no character is drawn. Webkit Nightly appears to have a bug such that it does not properly render non-BMP Unicode codepoints in vertical writing modes.
Unicode database values are shown for each character: the East Asian Width, General Category and Script.