Jlime$ opkg update
Downloading http://jlime.com/downloads/repository/muffinman/ipk/mipsel//Packages
Updated list of available packages in /var/lib/opkg/packages-mipsel
Downloading http://jlime.com/downloads/repository/muffinman/ipk/all//Packages
Updated list of available packages in /var/lib/opkg/packages-all
Downloading http://jlime.com/downloads/repository/muffinman/ipk/ben-nanonote//Packages
Updated list of available packages in /var/lib/opkg/packages-ben-nanonote
Downloading http://jlime.com/downloads/repository/extra-packages/nanonote//Packages
Updated list of available packages in /var/lib/opkg/packages-extras-nanonote

Jlime$ opkg list | grep gnuplot
gnuplot - 4.2.4-r1 - Gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility.
gnuplot-dbg - 4.2.4-r1 - Gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility.
gnuplot-dev - 4.2.4-r1 - Gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility.
gnuplot-doc - 4.2.4-r1 - Gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility.
gnuplot-x11 - 4.2.4-r1 - X11 display terminal for Gnuplot.
gnuplot-x11-dbg - 4.2.4-r1 - Gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility.