Contrary to the way the name sounds, the human humerus is not the same as the somewhat mythical "funny bone". The humerus is the bone in the upper part of your arm. It is a vitally important bone that allows you to move your arm - which in turn, allows you to do a variety of tasks, like catching food and eating it - among other things. To help with these movements, there are several muscles attached to the human humerus.
Interestingly, a muscle must cross a joint in order to move that joint. This means that the muscles which are attached to the humerus must also be attached at another point across either the shoulder or elbow joint. Contraction of the muscle then moves the joint.
Two larger muscles that attach to the humerus are the triceps and anconeus. They attach to the backside of the humerus and are involved in extension of the forearm. Triceps are particularly visible when they become large.
Four of the more important muscles that attach to the humerus make up a group called the "rotator cuff". The joint that attaches the humerus to the scapula, called the glenohumeral joint, is very mobile (you can rotate your arm in a wide range of movement), but it can dislocate relatively easily. The rotator cuff muscles help prevent these dislocations, among other things.
The rotator cuff muscle all attach to the humerus and include the teres minor, supraspinatus, infraspinatus, and subscapularis.
There are three muscles attached to the humerus which help flex the elbow. These are the brachialis, brachioradialis, and coracobrachialis. Interestingly, the biceps, which is the most visible muscle that runs next to the humerus, does not actually attach to the humerus.
The chest and trunk muscles that attach to the humerus include the teres major, latissimus dorsi, and pectoralis major. The pectoralis major is your primary "chest muscle", and is easily one of the most prominent muscles in the human body, particularly if you're at the beach.
The last important muscles that attaches to the humerus is the deltoid. This is your shoulder muscle and sits on the side of your upper arm. It helps you raise you arm to the side and over your head.
So there you are, some of the more important muscles that attach to the human humerus. Of course, this article isn't meant to go in to great detail about each of these muscles, but instead serves as more of an outline to the topic. Anatomy can be tremendously complicated and truly understanding it typically requires pictures or a cadaver.