I have my daughters half the week so, now that it is summer, I like to greet them with some home-made ice cream. The trick has always been how to make it without ice crystals. I find that three things do the trick:
One, after making the custard, chill it in the fridge over-night. I think this is the most important part - not only do you want to make sure the custard is very cool throughout, but I think settling for 8+ hours does something to it chemically that reduces ice crystals.
Two, when churning it, the shorter the churn, the smoother the end product. Meaning, churning smaller batches so it thickens more quickly (preferably in 20 minutes or less). In the maker I have (which is standard size), I find that churning two pints or less at a time makes a really creamy product.
Three, I've started adding a bit of guar gum, which gives it a bit of that nice store-bought "chewy-creaminess." This isn't necessary if you're going to eat the entire batch the day you make it, but helps if you're going to freeze it overnight.