How about a visit to the vet?

Is it fresh blood on the feces? or is it dried blood in the feces?
Fresh blood could indicate delicate blood vessels at the anus have been
torn... not necessarily serious.
Dried blood could indicate something wrong further inside the intestines
- serious, need vet attention.
I would recommend a visit to the vet anyway :-)
Camilla

Stop having anal sex with your cat, you are fooling no one.

James Marz

Born in lust, turn to dust.
Born in sin?  come on in! - Stephen King

Could be worms, could be hemorrhoids, could be something more serious. A
visit to the vet is a good idea.

W

Gee, what would you do if you noticed blood in your stool?  Post a
message here or go and see your physician?  

Take the animal to a vet.  Let a qualified professional deal with
this, not people on a board you know nothing about who can't see the
evidence you are talking about.

While I do think seeing a vet is a good idea, I am also well aware
that many people are on a tight budget and cant run to the vet
everytime fido or kitty gets a scratch, nor can they always go to the
doctor because they themselves have a stomach ache.  So, it's easy for
others to simply say "go to a vet" and spend your money for you.  I'm
sure you already considered going to a vet, because unless you are a
complete idiot, that's normally what comes to mind when an animal is
ill.  Obviously, you posted on here because you are trying to solve
the problem on your own if possible, and I totally understand that.
Personally, I think a GOOD animal owner will take the time to learn to
care for their own animals, instead of just relying on a vet or other
professionals, because there could come a time when you cant get the
vet there in time to help, and you must treat the animal yourself.  I
had that exact thing happen last winter during a blizzard.  I live on
a farm in a very rural area.  The nearest vet is 30+ miles away.  My
childs pony becomes severely ill.  I know exactly what is wrong with
the pony, and it was serious, and could be fatal.  I can not reach the
vet, and only get the message machine.  I started doing first aid,
knowing what to do.  I then call the vet again, and finally got him.
He had just gotten home, and was stuck in the snow.  He had just
transferred his messages to his home.  He said there was no possible
way he could get to my farm during that storm.  I told him what I had
done, he said that was good, suggested some medication that he gives
me in advance (just for times like this).  I begged and pleaded that
he try to make it here, but knew it was futile.  That's when I came to
my senses and said to him "I know what to do, I know what you'd do, I
have limited equipment on hand, guide me thru it over the phone".  I
brought the pony next to the house so I could talk on the phone while
I treated him, and did it.  That pony is alive today, and I did it
myself.  In fact the vet said he was amazed, especially since, as he
said "I sounded too upset to handle the treatment, when I first
called".  And, he was right, but I knew I had to do it, and I did, and
it was pretty risky doing this procedure being an amateur.

With that said, I do think it would be best to see a vet if you can.
However, you posted to get an answer, and here is mine.  I would
normally highly suspect worms.  I have been thru that already, and
yes, there was bloody stool.  However, it could also be hemorroids
<sp>.  You can often see hemorroids using a magnifying glass, and
spread the cats anus apart.  Look for sores and raw areas.  If you see
this, clean well, and apply some triple antibiotic ointment for
several days.  Also add some vegetable oil to the feed for several
days to lubricate and soften the stool.  I'd also cut back on dry
food, and offer more canned food. You also want to encourage the cat
to drink water, (to prevent hard stool).  Add a small amount of salt
to his feed (1/3 teaspoon).   If you do not see hemorroids, deworm the
cat according to the directions.  I'd still add some oil to the feed.

If there are no hemorroids, and deworming does not solve the problem,
then you have no choice but to see a vet, since the problem is
internal and there is nothing you can do yourself.  However, if the
blood is fresh, it is most likely one of these two things.  Since you
said the cat is active and has good weight, I am less likely to
suspect worms, which leaves the hemorroids.  So, if you can stomache
it, spread kittty's anus and look for the problem, and do as I say.

Hope this helps.

An Animal Lover