Sony Ericsson's quad-band S500i slider is available for free on operator contract. Among its selling points are its sidelights and ever changing themes. In the phone settings you can choose between themes which change as the seasons do, or as day turns into night.
Personally, I'm not sure about some of the themes. Driving rain falling on a tree which has lost many of its leaves for an autumn theme is hardly likely to be very inspirational to owners of this phone, and anyway, automatic theme changing with the seasons seems a bit, well, long term. But the day/night theme is actually quite fun and I do have a bit of a soft spot for animated themes in general.
As to the sidelights. Well, these amount to illuminated lights on the left and right edges of the phone, which can be set to glow in different colours depending on what is happening.
Now, gimmicky though it is, this could be quite useful when the phone is in silent mode, but Sony Ericsson doesn't take it far enough. You can choose a colour for incoming calls, but that's all. Had you been able to assign different colours to callers - favourite friends, work colleagues, significant other etc, then it could be quite handy. But no. Sony has hampered what could have been a handy little feature.
That assessment is pretty much applicable to the rest of this phone, which is average rather than outstanding all round.
Sony Ericsson seems to have had something of a brain-ache when deciding how to describe the colours of this mobile. Mine was ‘mysterious green', while you can also get it in ‘spring yellow'. The mysterious green livery is in fact comprised of a black outer casing with silvery grey around the edges. The green, a rather nice lime colour, comes into play when you open the slide, as it forms the number pad keys and their surround. It is also the illumination colour round the navigation button.