After a hard winter, your home sweet home may be in need of more of a bath than rain can provide. Spring might be a good time to look into borrowing a pressure washer to wipe away all the grime.
Certain kinds of siding can't take the pressure (same goes for peeling paint), so make sure you've got the right type and you'll be good to go. A pressure washer can also come in handy for greasy driveways and wooden decks -- just check to see that you've got the right amount of pressure for each job.
Tip: Don't have a friend with a pressure washer? Check your local hardware store to see if you can rent one. Not only will you get the benefit of a good wash, but (with hope) good advice to go with it.