An ATV is perfectly useful for getting from place to place or having a fun time on the trails, but to get some serious work done, you'll need some attachments.
There are lawn-mowing attachments that go either ahead of or behind the ATV. Some models have their own motors to power the blades. Trail-behind mower attachments sometimes use an offset tongue so the mower actually runs beside the ATV. This lets the ATV drive on the grass that's already been mowed instead of plowing through the tall weeds.
A winch is a crucial ATV accessory. It will let you drag heavy logs off the trail, and it'll pull the ATV itself through deep mud.
An ATV can double as a miniature snow plow with a plow attachment. The plows attach to an ATV's winch, which allows the plow to be raised and lowered. If you're dealing with a lot of snow, you can get a snow blower attachment. Like mower attachments, these accessories have their own motors. To dodge all that flying snow (or any that might be falling), you can get a soft-top "cab" that encloses the rider.
If you need to smooth out a dirt road or driveway, or groom your homemade motocross track, there's a variety of graders and blades that can be mounted to an ATV. With these, you can turn your ATV into a giant shovel or a powered rake. If you're doing some gardening, you can till soil or use a seed spreader attachment. Later in the season, you might want to pull a sprayer to apply an even coat of fertilizer.
Since ATVs don't have the cargo capacity of UTVs, cargo trailers can be very useful. Heavy-duty ATVs can pull up to 1,000 pounds (454 kilograms), so the best trailers use large, soft tires that disperse all that weight without sinking into the ground or churning up your lawn.