A few years ago I used another blog to write about "More PHP power on the command line" almost 5 years later the PHP interactive shell got a major update which went in PHP's trunk. The commit message tells a lot about the improvements:

- Improved CLI Interactive readline shell (Johannes)
  . Added cli.pager ini setting to set a pager for output.
  . Added cli.prompt ini settingto configure the shell prompt.
  . Added shortcut #inisetting=value to change ini settings at run-time.
  . Don't terminate shell on fatal errors.

A pager can be a an shell command which will receive the command output on its
STDIN channel

php > #cli.pager=less
php > phpinfo();
(output will appear in the pager)
php > #cli.pager=grep -i readline
php > phpcredits();
Readline => Thies C. Arntzen
php > #cli.pager=
(output appears again direct on the terminal)

A prompt can contain a few escape sequences like

php > #cli.prompt=\e[032m\v \e[031m\b \e[34m\> \e[0m
5.3.99-dev php > //Colorful prompt with version number

A prompt can also contaian PHP code in backticks

php > #cli.prompt=`echo gethostname();` \b \>
guybrush php >

But I assume a screenshot is quite useful, so here it goes:

So what doyou need to use this feature? - PHP trunk compiled using --with-readline or --with-libedit.The PHP Documentation has information about the interactive mode, the new features will be added once trunk is closer to a release and it's clear in what release this will appear.