"Happy as Larry" is a common idiom used to describe someone who is incredibly pleased or content. However, there are many other ways to express such a sentiment. For instance, one could say they are "over the moon," "walking on air," or "on top of the world." Other similar expressions include "in seventh heaven," "ecstatic," and "delighted." Alternatively, one could say they are "joyful," "gleeful," or simply "happy as can be." Each of these phrases has its unique connotations and inflections, so choose the one that best reflects your mood and situation.