Torre Catalunya Hotel

An absolute pleasure. I had been to Barcelona once before in the middle of winter, and while it was still a very nice trip concentrating on the cultural face of the city, Barcelona is very much a city to be experienced in the summer. It's size, large but with a fairly concentrated centre, make it a perfect place to idly wander on a warm late-summers' day.
The food was splendid (particularly at one of the outdoor tables at the beachfront restaurant Bestial - booking essential), as was the drink (of which a not inconsiderable amount was imbibed at various street-side cafe's). I would recommend getting off the beaten tourist track and heading to areas that the locals frequent, as you can effectively halve your eating and entertainment costs by doing this.
Our hotel, Torre Catalunya was superb; a four-star hotel which we got a last minute deal on for a double at £50/night. Housed in a very tall building, the hotel has its dining room on the top floor, and so we were afforded a splendid view of downtown Barcelona over breakfast. The rooms were clean and well appointed, and the ensuite was marvellous. Definitely earns it's star rating.
Barcelona is a place to spend some time. Give it a week rather than a weekend, and take the time to check out some of the areas outside of Las Ramblas or the waterfront. Of particular merit is a daytrip to the mountaintop monastery of Montserrat: a small detour out of Barcelona you won't regret.