Starting Seeds Indoors

We're researching a variety of options for starting seeds in our two locations. We've learned that heat is most important for seed germination followed by light. However, heating units specially designed for seed starting are costly. We checked the internet for frugal ideas and found some of the following suggestions:

-Electric blankets or heating pads. Some people do this, but most felt it could be dangerous for many reason. Could be a disaster. We agree.

-The top of the fridge. A warm spot which would work well, but space is limited. We might use this idea for some of our seeds.

-DIY warming unit made from a tote, tube lights and kitty litter. This possibility is intriguing. As luck would have it, Caroline's Dad had an unopened package of tube lights he donated to the cause.

-A crock pot/slow cooker. Michele came up with this creative idea, so we googled it. Someone else had tried this method and said it worked well.  Affordable crock pots are readily available at thrift stores.

-We're saving recyclables to be re-purposed into seed starting pots and other helps.

Caroline has a large picture window with baseboard heat underneath. She's thinking this is the ideal place to start seeds if a proper table can be found for the space. Perhaps her new little portable greenhouse could be used until outside temps are warm enough to move it  out to the deck.

Michele will start her seeds at her business where she has large glass windows. She's wondering about Portland's frequent overcast days and how this will effect the seedlings. Will grow lights be necessary?  Many options exist for rigging grow lights. Read a great article over at Simple, Green, Frugal, Co-op here.

We're wondering how all these devices will impact our electric bills. And how did people start seeds indoors in the days before electricity?