The functionality of the Sequence View can be significantly increased with Sequence View Extensions. Below is the demonstration its functionality.
The Circular Viewer shows the circular view of a sequence:

The 3D Structure Viewer adds 3D visualization for PDB and MMDB files:

The Chromatogram Viewer adds support for chromatograms visualization and editing:

The DNA Graphs Package shows various graphs for sequences:

The Dotplot provides a tool to build dotplots for DNA or RNA sequences.

A number of other instruments add graphical interface for popular sequence analysis methods:

For details see the next sections of the documentation: