...and I'm having an issue with memory usage. I got an alert from our sun management console that the box is at 90% memory usage. I need to know what's eating up the memory as this particular box has 16GB of RAM.
At least post the output of uname -a so folks know what model and OS level you have. A clue or two about what you run on the box would also help.
Luckily my mind reading powers are working.... you have a sunfire V240 running Solaris 8 and you are running Oracle on it. When a big database server is low on memory, I always check the shared memory segments.
ipcs -mb
will do it. 
Sorry for the lack of information, but like I said, I'm new to SunOS. Here's the output from the commands you gave. You mind reading powers were almost right on the money
<Host><root></>
$: ipcs -mb
IPC status from <running system> as of Wed Mar 11 20:21:48 EDT 2009
T ID KEY MODE OWNER GROUP SEGSZ
Shared Memory:
m 5 0xa5643354 --rw-r----- oracle dba 10657726464
<Host><root></>
$: uname -a
SunOS FoxHill 5.10 Generic_125100-09 sun4u sparc SUNW,Sun-Fire-V490
I'm assuming from the output that oracle is eating up all the memory.
Dang... I should have bought a lottery ticket. 