Treadmills are great for running and walking on. In most cases older people or people that have problems with their knees are told by their Doctors to get a treadmill instead of actually walking or jogging on asphalt. Treadmills are like shocks to your knees, they help stabilize your knees, and are a lot softer to walk on than say, the sidewalk or road. Treadmills can help strengthen your knees, and they also give you a really great cardio work out. An elliptical on the other hand also do the same thing, but they also really get your heart pumping and work as a great aerobic exercise as well.

There are several different kinds of elliptical machines as well as treadmills. Some of these machines are really high tech and include things like iPod hook ups, LED screens, cooling fans and much more. Another great thing about these two products in general is if you live in a small dwelling, you can actually buy a "folding" elliptical or treadmill. These allow you to easily place the elliptical or treadmill in a corner or even under a bed for that matter. When I lived in New York, I rented this really tiny studio, there was absolutely no way I could have had a non folding treadmill! So I bought this really nice Nordic Track one, it tucked away really nicely when I didn't need it and was easy to re-setup when I did want to use it. So you see you don't need a ton of room for these machines! No more excuses! Listed below are a few different elliptical machines as well as treadmills.

Nordic Track C2255 Treadmill -
ClearView Blue Back-lit Display built into treadmill console
2.25 CHP DurX Commercial Drive System
0-10 MPH 1-Step Speed Control
0-12% 1-Step Power Incline
20" x 55" Extra-Broad Treadbelt
6 Workout Programs
EKG Heart Rate Monitoring
The C 2255 includes an AutoBreeze fan
Carb Counter
Workout Intensity Meter
Odometer with MyMiles Tracker
iFIT compatible
3-position adjustable cushion deck
300-lb. weight capacity
NordicTrack Warranty
Lifetime Motor Warranty
One Year Parts/One Year In Home Labor Warranty

Proform 650 T Spacesaver -
SpaceSaver Design
Workout Programs
Heart rate monitor
Upper body workout
Fan
Console Display
iPod/MP3 compatible
Crystal clear sound
Resistance settings
Console

Sole F83 Treadmill -
Motor: 3.0 HP Continuous Duty, DC type, Ultra High Torque
Speed: 0.5 to 12 mph
Incline: 15% maximum, rack and pinion gear design
Weight: 260 lbs.
Deck Size: 33 X 78 - Cushion Flex Shock Absorption Whisper Deck
User Weight: 375 lbs.
Running Surface: 20 X 58
Belt: Double Woven 2 Ply
Rollers: 2 3/4 inches
Folding: Yes, with the Easy Assist folding feature
Heart Rate Control: Yes with wireless chest strap included
Hand Pulse Grips: Yes, and arm rest speed/incline controls
Display Color: Tri Color: Red, Green and Gold
Message Window: Yes - Scrolling Information
Standard Programs: Six
User Defined Programs: Two
Heart Rate Programs: Two
Cooling Fans: Yes

If you are looking for some reviews as well you can take a look at the following places for more information, prices, feedback and much more:
Elliptical Trainer Review
Fitness Equipment Source
All Ellipticals
Treadmill Doctor
Treadmill Adviser