The list is taken from cnet.com and is updated regularly. Here are the current winners/losers…note that the numbers next to the phones are the SAR (specific absorption rate)…the higher it is the more radiation:
 
Ten lowest-radiation cell phones
 
Manufacturer and model SAR level
(digital)
1. LG KG800 0.135
2. Motorola Razr V3x 0.14
3. Nokia 9300 0.21
4. Nokia N90 0.22
5. Samsung Sync SGH-A707 0.236
6. Nokia 7390 0.26
7a. Samsung SGH-T809 0.32
7b. Motorola Razr2 V9 0.32
8. Bang & Olufsen Serene (Samsung SGH-E910) 0.33
9. LG VX8350 0.348
  
Ten highest radiation cell phones:
 
1. Motorola V195s 1.6
2. Motorola Slvr L6 1.58
3a. Motorola Slvr L2 1.54
3b. Motorola W385 1.54
4a. Motorola Deluxe ic902 1.53
4b. T-Mobile Shadow (HTC) 1.53
5a. Samsung Sync SGH-C417 1.51
5b. Motorola V365 1.51
5c. RIM BlackBerry Curve (AT&T) 1.51
6. Sanyo S1 1.48
 
cnet.com reviews