In 2008, LEGO released 7 Power Functions sets across 2 subthemes, all of these sets have been retired. Subthemes for that year included Accessories and Technic. For that year, the total price of all retail sets cost $82, today those sets are valued around $298, a growth of 264%.
Most valuable 2008 LEGO Power Functions set
8293 Motor Set $100.00
Highest growth 2008 Power Functions set
8886 Extension Cable 20cm +542.47%
7 sets

8293 Motor Set

Theme / Subtheme Power Functions / Technic
Year 2008
Pieces 10
Availability Retired
8293 LEGO Power Functions Technic Motor Set
Retail $29.99
Value $100.00
Growth  +233.4%
Annual growth 9.5%

8881 Battery Box

Theme / Subtheme Power Functions / Accessories
Year 2008
Pieces 1
Availability Retired
8881 LEGO Power Functions Battery Box
Retail $6.99
Value $39.99
Growth  +472.1%
Annual growth 14.3%

8882 XL-Motor

Theme / Subtheme Power Functions / Accessories
Year 2008
Pieces 1
Availability Retired
8882 LEGO Power Functions XL-Motor
Retail $9.99
Value $46.22
Growth  +362.7%
Annual growth 25.8%

8883 M-Motor

Theme / Subtheme Power Functions / Accessories
Year 2008
Pieces 1
Availability Retired
8883 LEGO Power Functions M-Motor
Retail $7.49
Value $37.70
Growth  +403.3%
Annual growth 10.7%

8884 IR Receiver

Theme / Subtheme Power Functions / Accessories
Year 2008
Pieces 1
Availability Retired
8884 LEGO Power Functions IR Receiver
Retail $14.99
Value $23.83
Growth  +59.0%
Annual growth 3.6%

8885 IR Remote Control

Theme / Subtheme Power Functions / Accessories
Year 2008
Pieces 1
Availability Retired
8885 LEGO Power Functions IR Remote Control
Retail $9.49
Value $31.02
Growth  +226.9%
Annual growth 6.9%

8886 Extension Cable 20cm

Theme / Subtheme Power Functions / Accessories
Year 2008
Pieces 1
Availability Retired
8886 LEGO Power Functions Extension Cable 20cm
Retail $2.99
Value $19.21
Growth  +542.5%
Annual growth 13.3%