Hi,
Many fonts have alternative glyphs for some unicode codepoints. These glyphs can be accessed by enabling OpenType tables such as 'salt', 'ss01', etc. Inkscape has supported using such alternative glyphs through the 'Variants' tab of the 'Text and Font' dialog (under the last section, 'Feature Settings'). But one problem that was pointed out is that it is difficult to know what alternative glyphs are available for a particular font. I've just added code in trunk that will display such alternative glyphs in the 'Feature Settings' section. The GUI leaves a bit to be desired and there is some more work to do to show all alternative glyphs properly (for example, font style is ignored) but it is a start.
Please test it out and give me your feedback.
Tav