Honeywell offer a wide range of both warm mist and cool mist humidifiers for your house or office.
Most models have a built in humidity meter, to ensure that your room stays at peak humidity at all times.
Most Honeywell humidifiers also have an auto-shut-off feature for when they run out of water. This is a useful feature that is lacking in the smaller models of most other brands.
Parts and filters are easy to find.
Models reviewed on this site:
Honeywell QuietCare HCM-6009 - A console humidifier with 9 gallons per day output and a lot of desirable features.