Solar powered trickle chargers

[inmate]

Since taking up cycling again in an attempt to address
the "Battle of the bulge" my car remains on the driveway for several days without use, this causes
battery drain through the alarm/immobiliser. I have recently heard of solar powered trickle chargers which
consist of a solar panel you put on top of the dashboard and plug into the cigar lighter. Has anyone had any experience with these? and are they any good?

[shadowninja]

mine seemed to work when i went on holiday for a couple of weeks...

[mel]

They're crap with the car garaged

[shadowninja]

easy solution. leave the garage light on then!

[HiRich]

I use the Punto very infrequently, and even with the alarm off (immobiliser on) the battery would be flat in two weeks, and need a new battery at least once a year (bit of a pain when I do only 1,000 miles)
I bought an expensive one from Airflow (www.racecar.co.uk/airflow), though a much cheaper one is available from Demon Tweeks and possibly Halfords.
I now get 4 weeks plus, with still ample power to spin the starter properly. So, yes, they are bloody good.
Two tips:
1- Pre-check that your ciggy lighter remains live when the key is out (not all are)
2- make sure a ciggy lighter adapter is included (not standard on the Airflow one)

Only problem now is that I need to fit a cover to protect that Italian excuse for paint...