db-thermometer is a jQuery UI plugin which provides a vertical strip
meter which resembles a thermometer for displaying sound pressure
levels. See the demo.html file for an example of how it is used. 

Other noteworthy things to mention:

* The usable range of the widget is from zero to a few hundred dB. The
  CSS would need to be tweaked for 4-digit limit values, for example.

* The value makers on the right-hand side of the widget are displayed
  when the values are divisible by 5. The yellow/red transition values
  can be set to anything within the widget's min/max range.

* When values under or over the widget's min/max range are set, the
  pointer will display the min/max value preceded by a < or >,
  respectively. 

* The pointer graphic and text sizes are not particularly sexy, but
  were functional for the original application this widget was used in.

db-thermometer was written by Scott Garman <sgarman@zenlinux.com> and
is freely distributed under the terms of the GNU Lesser GPL license v3.

Fork freely, share and enjoy.