OK, so I'll admit it,I'm kind of a biology nerd (and major, in case you're interested), but dendrites are really cool!
Did you know that dendrites are covered in smaller dendritic spines that hold the synapses to receive information during neurotransmission. The number and size of these dendritic spines is different for each dendrite.
Also, dendritic spines are constantly growing and shrinking. Drug use can have a big impact on the length and number of dendritic spines. Alcohol and morphine are two drugs that have been shown to shrink dendrites and dendritic spines, while feel-good substances like nicotine, cocaine, and amphetamine can increase their number and size -- whenever I think of that I kind of imagine the dendrites like seaweed, in motion. It's a bit creepy to think about all that going on in your body though, right?
Oh, one more fact -- reduced size and number of dendrites in the brain is related to many psychiatric disorders like depression, anxiety, and schizophrenia. This may be why it is so hard for smokers to quit smoking and for drug addicts to stop using.