Are there any good R object browsers?

Question

S-Plus has a great object explorer and data editor built into its GUI. It allows you to easily see all the objects in the workspace at a glance, and sort them by name, size

Answer 1

What about Rattle?

Rattle stands for R Analytical Tool To Learn Easily. According to the website Rattle ''is a popular GUI for data mining using R. It presents statistical and visual summaries of data, transforms data that can be readily modelled, builds both unsupervised and supervised models from the data, presents the performance of models graphically, and scores new datasets.''