Spell without component?

[CrepeUscule]

So, for a new game, i am going to a stealthy sneaky build, with some splash of caster (probably bard/rogue for starter).
I thinked of some way to deal a decent sneaky touch attack and i think i'm going to use a lot silent sound (Book of Eldritch Might, p 26), only a somatic component, sound dmg and touch attack, why not?
And now i wonder... why not make it one step higher, and use still metamagic on it?

And here come my questions :

1) Is it even possible to have a spell without any component, like this exemple or by combo silent/still metamagic?
2) If yes, does it work basically only by mind, and so usable in every situation till i'm conscious?
3) Still if yes, is there any visible sign that i'm the user of the spell, without detect magic/arcane sight?
4) What if i use the skill trick conceal spellcasting, same situation or anything different?

[Necroticplague]

1) Is it even possible to have a spell without any component, like this exemple or by combo silent/still metamagic?
2) If yes, does it work basically only by mind, and so usable in every situation till i'm conscious?
3) Still if yes, is there any visible sign that i'm the user of the spell, without detect magic/arcane sight?
4) What if i use the skill trick conceal spellcasting, same situation or anything different?

1. Yes, why wouldn't there be? You've proven that it's possible already, Silent Flare is another example.
2. Essentially, yes, barring any Concentration issues. Just like how a psionicist can manifest as long as they can think straight.
3. Yes, there is. Casting a spell without components still requires you to concentrate noticeably (since it still provokes AoOs).
4. Conceal Spellcasting is unrelated to components. If you use it, it's sleight of hand vs. spot to notice you casting, regardless of all other circumstances, including components.

[Gildedragon]

Slap on invisible spell. Level Adjustment +0 for colorless fire... And possibly invisible monsters

[happycube]

Along the same lines as the Conceal Spellcasting skill trick, page 117 of the Rules Compendium mentions the "Unobtrusive Spellcasting" use for sleight of hand, which should allow you to cast unnoticed by any that fail their spot checks.

[Firest Kathon]

It seems to me that you are playing 3.5, but on the off chance that you are playing Pathfinder instead: The Unchained Rogue can get the Minor Magic rogue talent and pick up a level 0 spell (e.g. Acid Splash) as an at-will spell-like ability (which has no components in the first place).

[bean illus]

Should i mention that Beguiler is a skill monkey, full caster, that gets silent and still as bonus feats, and sneak attack ... ?

[Rebel7284]

Should i mention that Beguiler is a skill monkey, full caster, that gets silent and still as bonus feats, and sneak attack ... ?

It does not grant sneak attack.

[Kaleph]

Should i mention that Beguiler is a skill monkey, full caster, that gets silent and still as bonus feats, and sneak attack ... ?

The beguiler doesn' get sneak attack.

Coming back to the original post, I think the single class, that does everything that you want, is the psychic rogue. You just need hidden talent to get energy ray, and you're done.

It has a pretty decent sneak attack (probably more than a dual-class'd rogue), it provides most of the other rogue signature features (including trapfinding), full manifesting and obviously without any components, powers up to 5th level from a nice selection, 6 skill point per level.