Giving my tomatoes and peppers a day in the sunshine. They are at the 6 week mark and still doing beautifully.
On a related note, here is the mini "greenhouse" I bought last year. I'd scoured the internet and researched and researched, finally finding it at my grocery store, of all places. I bought it and a year later, I can say it was a colossal waste of money. In fact, if I wasn't storing my seed domes and trays in it right now, I'd probably get rid of it.
The open shelving that's sitting next to it is really all I need for a place to set out some seedlings to harden off or get some sun. Our weather here is so mild, we don't need this plastic cover. In fact, the plastic cover becomes a hazard because it gets too hot and prevents the air circulation seedlings need, which is one of the reason you'd want to give them outside time in the first place.
So if you're considering one of these, unless you plan on putting seedlings out in the snow, don't waste your money. The light set-up I put in the shed has been the perfect situation for the seeds. They get light and heat from the lights, but the shed also shades them in the event it turns hot on me during the day. I open the windows to give them air, and when I'm home on the weekends, I set them outside to give them fresh air. No need for fancy, rikety, shelves that blow over at the slightest breeze.
In fact, now that I've said all this, I think I am going to take it apart and toss it!