It's a bit cold in the UK at the moment and if you don't have heated grips you might be interest in some Hot Hands. I fitted mine today.
The kit consists of a switch, two velcro over-grips and a wiring harness that you connect direct to your battery (with an inline fuse).
Fitting is simple. On the Elefant (or any other bike)...
1 - pop the saddle, connect the battery terminals
2 - route the wire to up around the handlebars
3 - zip tie the switch to the bar
4 - wrap the overgrips around the grips and velcro them together
5 - plug the wires together
The switch and connector:
I took the bike for a ride in the snow
to see how they worked...
They heat up in 30 seconds and get hot. Oxford recommend using winter gloves with them as they really do get hot. I used summer super-moto gloves and after 5 minutes my hands would start to get uncomfortably hot (this was at about 1C). There is no temperature control so it's a case of turning them off. It takes another few minutes for everything to cool down again.
I'm sure with winter gloves, you could leave them on (or at least leave them on for longer) but flicking the switch every few minutes works fine.
On a technical note they draw just 18W so shouldn't have a negative effect on the charging system, but as they're wired directly to the battery they stay on even with the ignition off, so make sure you really have turned them off after a ride.
The only downside is the amount of wire from the switch to the grips. Oxford must have designed the grips for bikes with the world's biggest ape-hangers. There's a couple of feet of wire left spare. I wrapped mine around the bars and secured it with some electrical tape. Not pretty. I guess this doesn't really matter as I'll only ride the bike a couple of times in the winter and they'll come off again.
Overall... I like them. A lot.