Main Green Party pledges at this election:
- Replace VAT with eco tax
- Invest in renewable energy
- Tax on aviation fuel
- Cut CO2 emissions by 20% by 2010
- Recycle 60% domestic waste by 2010
- Higher tax on incomes over £50,000
- Oppose PFI schemes
- Ban GM foods
- Produce 30% food organically by 2012
- Replace council tax and uniform business tax with land value tax.
You can read a full PDF version of the Green Party manifesto here; it covers England and Wales only, though, not the whole of the UK. I doubt if this is the election when the Green Party will make a major breakthrough, though.