The laser toy is much loved, but also toy mice, which they bat around the laminate floor, ping pong balls, anything like that. Plastic milk bottle lids are popular. In particular I have this mouse family on springs on a base - I have to stand that back up twice a day so they must play with it. Also, they love their catnip cushions (sold for North Herts CP), but your little one won't be old enough for catnip yet - try it at about a year old or so. Fishing rod toys are good, but try not to let them chew the string or they won't last long (Hestia's record is two days) and never leave these (or the laser toys) with the cats. They also love their cat tree - I would avoid the argos ones in the long term as I have had two and neither lasted long (second one only a week before the top part broke). If its all you can afford, buy one and save up for the (inevitable) replacement. You can find them cheap every so often - the one Lidls sell when they have their pet offers seems good (so far - not had it long).
General rubbish is good - cardboard boxes, screwed up paper, the plastic seal from round the ben and jerrys tub (although most of this stuff I throw away after a couple of days - there will be new bits later). As long as they can't swallow it or hurt themselves on it, or make a mess with it, they can play with it if they show interest. Some things I supervise (screwed up foil) whereas others are unlikely to do them any harm (the newspaper).
Every so often I hide treats round the house for them to find. I play with some toys with them, but some they like to play with themselves. Have had some disasters (they despise the crinkly jester hat and the wicker basket), but most things have gone down well.