You can always sell it to someone else who may want it.
As for the stocks: Most of them operate on the number of active people in a given group or Division, or something along those lines. Find out what the bond is based on and see if it's something that's likely to go up.
For example, the recent burst of activity in the Navy brought my bonds up from -9% to around +40%.
Note: Unfortunately, none of the Naval bonds have been available for quite some time. Most of them are tied up either in the portfolios of dead characters or those of the ancients who've been here forever.
-Drac