I find indoor plants very restful. I feel it makes your house look much better. Of course I am too cheap to get a large one, so I have a collection of small, pitiful plants rather than the major green room feature of my dreams, but there are some great garden bargains around at the moment.
At Aldi, 140mm indoor plants are $7.99. You can get (L-R) sago palms (in NSW, Victoria and ACT only), peace lilies, Zanzibar gems and magic beans.
At Bunnings, you can get a 130mm Easy Care Calathea Orbifolia for $8.24. These are quite nice-looking.
It's part of the Easy Care range of indoor plants that are all the same price. I guess it's a lottery which ones you get at various Bunningses.
Bunnings also has 30cm hanging baskets (with liner) for $3.98 and 35cm baskets for $5.36. These would be good if you only have a courtyard or balcony, but would still like some greenery.
And there are 'Grow Your Own' vegetable seedlings for $2.94 (which may include tomatoes, lettuce, capsicums, chilli, beans, peas, carrots, eggplant, sweet corn, silverbeet and zucchini), and 'Flying Start' 70mm perennial plants for $2.97.