Font Combiner unicode
Font Combiner accommodates the ISO 8859-1 character set.
The current interface also allows for the range
8352 - 8378 (x20A0 - x20BA) of the unicode currency symbols block and
57344 - 57411 (xE000 - xE043) of the unicode private use area.
Icon fonts are a popular way to include simple vector graphics on web pages,
citing Font Awesome
as two excellent examples.
To combine icons into a standard web font:
Unicode and how to use
The unicode private use area is a special unicode range left undefined by
the Unicode Consortium so that third-parties may define their own characters without conflicting
with Unciode Consortium assignments.
A custom unicode character added to a font can be used on the web by including an HTML entity reference.
For example, the entity reference 
included in an HTML document will reference the first slot
in the Unicode private use area. This is a decimal value. Some users may find it convenient to use the equivalent
hexadecimal value instead, 
This is a subset of Source Sans Pro Bold Italic, incorporating an icon from an icon font:
(this font also includes kerning)
As an alternative to direct use of HTML entities, it's possible to include HTML content through CSS.
This can be achieved with the use of a CSS2
:before or :after pseudo-elements.
For example, to include the same unicode character using CSS :after, you may use
content: " \E000";
to achieve a similar result:
Note that escaped CSS character references should always be set in hexadecimal.
The same system can also be useful if a font is missing a particular currency symbol:
Font Combiner is in active development and will include more unicode source options in due course.